bionic (1) jq.1.gz

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NAME

       jq - Command-line JSON processor

SYNOPSIS

       jq [options...] filter [files...]

       jq  can  transform  JSON  in  various ways, by selecting, iterating, reducing and otherwise mangling JSON
       documents. For instance, running the command jq ´map(.price) | add´ will take an array of JSON objects as
       input and return the sum of their "price" fields.

       jq  can  accept text input as well, but by default, jq reads a stream of JSON entities (including numbers
       and other literals) from stdin. Whitespace is only needed to separate entities such as 1 and 2, and  true
       and false. One or more files may be specified, in which case jq will read input from those instead.

       The  options  are  described in the INVOKING JQ section; they mostly concern input and output formatting.
       The filter is written in the jq language and specifies how to transform the input file or document.

FILTERS

       A jq program is a "filter": it takes an input, and produces an output. There are a lot of builtin filters
       for  extracting  a  particular  field  of an object, or converting a number to a string, or various other
       standard tasks.

       Filters can be combined in various ways - you can pipe the output of one filter into another  filter,  or
       collect the output of a filter into an array.

       Some  filters  produce  multiple  results, for instance there´s one that produces all the elements of its
       input array. Piping that filter into a second runs the second filter  for  each  element  of  the  array.
       Generally,  things that would be done with loops and iteration in other languages are just done by gluing
       filters together in jq.

       It´s important to remember that every filter has an input and an output. Even literals like "hello" or 42
       are  filters  - they take an input but always produce the same literal as output. Operations that combine
       two filters, like addition, generally feed the same input to both and combine the results.  So,  you  can
       implement  an  averaging  filter as add / length - feeding the input array both to the add filter and the
       length filter and then performing the division.

       But that´s getting ahead of ourselves. :) Let´s start with something simpler:

INVOKING JQ

       jq filters run on a stream of JSON data. The input to jq is parsed as a sequence of  whitespace-separated
       JSON  values  which are passed through the provided filter one at a time. The output(s) of the filter are
       written to standard out, again as a sequence of whitespace-separated JSON data.

       Note: it is important to mind the shell´s quoting rules. As a general rule  it´s  best  to  always  quote
       (with single-quote characters) the jq program, as too many characters with special meaning to jq are also
       shell meta-characters. For example, jq "foo" will fail on most Unix shells because that will be the  same
       as  jq  foo,  which  will generally fail because foo is not defined. When using the Windows command shell
       (cmd.exe) it´s best to use double quotes around your jq program when given on the  command-line  (instead
       of the -f program-file option), but then double-quotes in the jq program need backslash escaping.

       You can affect how jq reads and writes its input and output using some command-line options:

       •   --version:

           Output the jq version and exit with zero.

       •   --seq:

           Use  the  application/json-seq  MIME  type scheme for separating JSON texts in jq´s input and output.
           This means that an ASCII RS (record separator) character is printed before each value on  output  and
           an  ASCII  LF  (line  feed)  is  printed  after every output. Input JSON texts that fail to parse are
           ignored (but warned about), discarding all subsequent input until the next RS. This more also  parses
           the output of jq without the --seq option.

       •   --stream:

           Parse  the  input  in  streaming fashion, outputing arrays of path and leaf values (scalars and empty
           arrays or empty objects). For example, "a" becomes [[],"a"],  and  [[],"a",["b"]]  becomes  [[0],[]],
           [[1],"a"], and [[1,0],"b"].

           This  is  useful  for  processing  very  large inputs. Use this in conjunction with filtering and the
           reduce and foreach syntax to reduce large inputs incrementally.

       •   --slurp/-s:

           Instead of running the filter for each JSON object in the input, read the entire input stream into  a
           large array and run the filter just once.

       •   --raw-input/-R:

           Don´t  parse  the  input  as JSON. Instead, each line of text is passed to the filter as a string. If
           combined with --slurp, then the entire input is passed to the filter as a single long string.

       •   --null-input/-n:

           Don´t read any input at all! Instead, the filter is run once using null as the input. This is  useful
           when using jq as a simple calculator or to construct JSON data from scratch.

       •   --compact-output / -c:

           By  default,  jq  pretty-prints  JSON output. Using this option will result in more compact output by
           instead putting each JSON object on a single line.

       •   --tab:

           Use a tab for each indentation level instead of two spaces.

       •   --indent n:

           Use the given number of spaces (no more than 8) for indentation.

       •   --color-output / -C and --monochrome-output / -M:

           By default, jq outputs colored JSON if writing to a terminal. You can force it to produce color  even
           if writing to a pipe or a file using -C, and disable color with -M.

       •   --ascii-output / -a:

           jq  usually outputs non-ASCII Unicode codepoints as UTF-8, even if the input specified them as escape
           sequences (like "\u03bc"). Using this option, you can force jq to  produce  pure  ASCII  output  with
           every non-ASCII character replaced with the equivalent escape sequence.

       •   --unbuffered

           Flush  the  output after each JSON object is printed (useful if you´re piping a slow data source into
           jq and piping jq´s output elsewhere).

       •   --sort-keys / -S:

           Output the fields of each object with the keys in sorted order.

       •   --raw-output / -r:

           With this option, if the filter´s result is a string then it will be  written  directly  to  standard
           output  rather  than  being  formatted as a JSON string with quotes. This can be useful for making jq
           filters talk to non-JSON-based systems.

       •   --join-output / -j:

           Like -r but jq won´t print a newline after each output.

       •   -f filename / --from-file filename:

           Read filter from the file rather than from a command line, like awk´s -f option. You can also use ´#´
           to make comments.

       •   -Ldirectory / -L directory:

           Prepend  directory to the search list for modules. If this option is used then no builtin search list
           is used. See the section on modules below.

       •   -e / --exit-status:

           Sets the exit status of jq to 0 if the last output values was neither false nor null, 1 if  the  last
           output  value  was either false or null, or 4 if no valid result was ever produced. Normally jq exits
           with 2 if there was any usage problem or system error, 3 if there was a jq program compile error,  or
           0 if the jq program ran.

       •   --arg name value:

           This  option  passes a value to the jq program as a predefined variable. If you run jq with --arg foo
           bar, then $foo is available in the program and has the value "bar". Note that value will  be  treated
           as a string, so --arg foo 123 will bind $foo to "123".

       •   --argjson name JSON-text:

           This  option  passes  a  JSON-encoded value to the jq program as a predefined variable. If you run jq
           with --argjson foo 123, then $foo is available in the program and has the value 123.

       •   --slurpfile variable-name filename:

           This option reads all the JSON texts in the named file and binds an array of the parsed  JSON  values
           to  the  given  global  variable. If you run jq with --argfile foo bar, then $foo is available in the
           program and has an array whose elements correspond to the texts in the file named bar.

       •   --argfile variable-name filename:

           Do not use. Use --slurpfile instead.

           (This option is like --slurpfile, but when the file has just one text, then that  is  used,  else  an
           array of texts is used as in --slurpfile.)

       •   --run-tests [filename]:

           Runs  the  tests in the given file or standard input. This must be the last option given and does not
           honor all preceding options. The input consists of comment lines,  empty  lines,  and  program  lines
           followed  by  one  input  line,  as  many  lines  of  output  as are expected (one per output), and a
           terminating empty line. Compilation failure tests start with a line containing only "%%FAIL", then  a
           line  containing  the  program  to compile, then a line containing an error message to compare to the
           actual.

           Be warned that this option can change backwards-incompatibly.

BASIC FILTERS

   .
       The absolute simplest (and least interesting) filter is .. This is a filter  that  takes  its  input  and
       produces it unchanged as output.

       Since jq by default pretty-prints all output, this trivial program can be a useful way of formatting JSON
       output from, say, curl.

           jq ´.´
              "Hello, world!"
           => "Hello, world!"

   .foo, .foo.bar
       The simplest useful filter is .foo. When given a JSON object  (aka  dictionary  or  hash)  as  input,  it
       produces the value at the key "foo", or null if there´s none present.

       If the key contains special characters, you need to surround it with double quotes like this: ."foo$".

       A filter of the form .foo.bar is equivalent to .foo|.bar.

           jq ´.foo´
              {"foo": 42, "bar": "less interesting data"}
           => 42

           jq ´.foo´
              {"notfoo": true, "alsonotfoo": false}
           => null

           jq ´.["foo"]´
              {"foo": 42}
           => 42

   .foo?
       Just like .foo, but does not output even an error when . is not an array or an object.

           jq ´.foo?´
              {"foo": 42, "bar": "less interesting data"}
           => 42

           jq ´.foo?´
              {"notfoo": true, "alsonotfoo": false}
           => null

           jq ´.["foo"]?´
              {"foo": 42}
           => 42

           jq ´[.foo?]´
              [1,2]
           => []

   .[<string>], .[2], .[10:15]
       You can also look up fields of an object using syntax like .["foo"] (.foo above is a shorthand version of
       this). This one works for arrays as well,  if  the  key  is  an  integer.  Arrays  are  zero-based  (like
       javascript), so .[2] returns the third element of the array.

       The  .[10:15]  syntax  can  be  used to return a subarray of an array or substring of a string. The array
       returned by .[10:15] will be of length 5, containing the elements from index 10 (inclusive) to  index  15
       (exclusive).  Either index may be negative (in which case it counts backwards from the end of the array),
       or omitted (in which case it refers to the start or end of the array).

       The .[2] syntax can be used to return the element at the given index. Negative indices are allowed,  with
       -1 referring to the last element, -2 referring to the next to last element, and so on.

       The  .foo  syntax  only works for simply keys i.e. keys that are all alphanumeric characters. .[<string>]
       works with keys that contain special characters such as colons and dots. For  example  .["foo::bar"]  and
       .["foo.bar"] work while .foo::bar and .foo.bar would not.

       The  ?  "operator"  can also be used with the slice operator, as in .[10:15]?, which outputs values where
       the inputs are slice-able.

           jq ´.[0]´
              [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
           => {"name":"JSON", "good":true}

           jq ´.[2]´
              [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
           => null

           jq ´.[2:4]´
              ["a","b","c","d","e"]
           => ["c", "d"]

           jq ´.[2:4]´
              "abcdefghi"
           => "cd"

           jq ´.[:3]´
              ["a","b","c","d","e"]
           => ["a", "b", "c"]

           jq ´.[-2:]´
              ["a","b","c","d","e"]
           => ["d", "e"]

           jq ´.[-2]´
              [1,2,3]
           => 2

   .[]
       If you use the .[index] syntax, but omit the index entirely, it will return all of  the  elements  of  an
       array. Running .[] with the input [1,2,3] will produce the numbers as three separate results, rather than
       as a single array.

       You can also use this on an object, and it will return all the values of the object.

           jq ´.[]´
              [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
           => {"name":"JSON", "good":true}, {"name":"XML", "good":false}

           jq ´.[]´
              []
           =>

           jq ´.[]´
              {"a": 1, "b": 1}
           => 1, 1

   .[]?
       Like .[], but no errors will be output if . is not an array or object.

   ,
       If two filters are separated by a comma, then the input will be fed into both and there will be  multiple
       outputs:  first, all of the outputs produced by the left expression, and then all of the outputs produced
       by the right. For instance, filter .foo, .bar, produces  both  the  "foo"  fields  and  "bar"  fields  as
       separate outputs.

           jq ´.foo, .bar´
              {"foo": 42, "bar": "something else", "baz": true}
           => 42, "something else"

           jq ´.user, .projects[]´
              {"user":"stedolan", "projects": ["jq", "wikiflow"]}
           => "stedolan", "jq", "wikiflow"

           jq ´.[4,2]´
              ["a","b","c","d","e"]
           => "e", "c"

   |
       The | operator combines two filters by feeding the output(s) of the one on the left into the input of the
       one on the right. It´s pretty much the same as the Unix shell´s pipe, if you´re used to that.

       If the one on the left produces multiple results, the one on the right will be  run  for  each  of  those
       results. So, the expression .[] | .foo retrieves the "foo" field of each element of the input array.

           jq ´.[] | .name´
              [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
           => "JSON", "XML"

TYPES AND VALUES

       jq  supports  the  same  set of datatypes as JSON - numbers, strings, booleans, arrays, objects (which in
       JSON-speak are hashes with only string keys), and "null".

       Booleans, null, strings and numbers are written the same way as in javascript. Just like everything  else
       in  jq,  these simple values take an input and produce an output - 42 is a valid jq expression that takes
       an input, ignores it, and returns 42 instead.

   Array construction - []
       As in JSON, [] is used to construct arrays, as in [1,2,3]. The elements of  the  arrays  can  be  any  jq
       expression.  All  of the results produced by all of the expressions are collected into one big array. You
       can use it to construct an array out of a known quantity of values (as  in  [.foo,  .bar,  .baz])  or  to
       "collect" all the results of a filter into an array (as in [.items[].name])

       Once  you  understand  the  ","  operator,  you  can  look at jq´s array syntax in a different light: the
       expression [1,2,3] is not using a built-in syntax for comma-separated arrays, but is instead applying the
       [] operator (collect results) to the expression 1,2,3 (which produces three different results).

       If  you have a filter X that produces four results, then the expression [X] will produce a single result,
       an array of four elements.

           jq ´[.user, .projects[]]´
              {"user":"stedolan", "projects": ["jq", "wikiflow"]}
           => ["stedolan", "jq", "wikiflow"]

   Objects - {}
       Like JSON, {} is for constructing objects (aka dictionaries or hashes), as in: {"a": 42, "b": 17}.

       If the keys are "sensible" (all alphabetic characters), then the quotes can be left off. The value can be
       any  expression  (although  you may need to wrap it in parentheses if it´s a complicated one), which gets
       applied to the {} expression´s input (remember, all filters have an input and an output).

           {foo: .bar}

       will produce the JSON object {"foo": 42} if given the JSON object {"bar":42, "baz":43}. You can use  this
       to  select  particular  fields  of  an  object: if the input is an object with "user", "title", "id", and
       "content" fields and you just want "user" and "title", you can write

           {user: .user, title: .title}

       Because that´s so common, there´s a shortcut syntax: {user, title}.

       If one of the expressions produces multiple results, multiple  dictionaries  will  be  produced.  If  the
       input´s

           {"user":"stedolan","titles":["JQ Primer", "More JQ"]}

       then the expression

           {user, title: .titles[]}

       will produce two outputs:

           {"user":"stedolan", "title": "JQ Primer"}
           {"user":"stedolan", "title": "More JQ"}

       Putting  parentheses  around  the key means it will be evaluated as an expression. With the same input as
       above,

           {(.user): .titles}

       produces

           {"stedolan": ["JQ Primer", "More JQ"]}

           jq ´{user, title: .titles[]}´
              {"user":"stedolan","titles":["JQ Primer", "More JQ"]}
           => {"user":"stedolan", "title": "JQ Primer"}, {"user":"stedolan", "title": "More JQ"}

           jq ´{(.user): .titles}´
              {"user":"stedolan","titles":["JQ Primer", "More JQ"]}
           => {"stedolan": ["JQ Primer", "More JQ"]}

BUILTIN OPERATORS AND FUNCTIONS

       Some jq operator (for instance, +) do different things depending on the type of their arguments  (arrays,
       numbers, etc.). However, jq never does implicit type conversions. If you try to add a string to an object
       you´ll get an error message and no result.

   Addition - +
       The operator + takes two filters, applies them both to the same input, and  adds  the  results  together.
       What "adding" means depends on the types involved:

       •   Numbers are added by normal arithmetic.

       •   Arrays are added by being concatenated into a larger array.

       •   Strings are added by being joined into a larger string.

       •   Objects  are  added  by  merging, that is, inserting all the key-value pairs from both objects into a
           single combined object. If both objects contain a value for the same key, the object on the right  of
           the + wins. (For recursive merge use the * operator.)

       null can be added to any value, and returns the other value unchanged.

           jq ´.a + 1´
              {"a": 7}
           => 8

           jq ´.a + .b´
              {"a": [1,2], "b": [3,4]}
           => [1,2,3,4]

           jq ´.a + null´
              {"a": 1}
           => 1

           jq ´.a + 1´
              {}
           => 1

           jq ´{a: 1} + {b: 2} + {c: 3} + {a: 42}´
              null
           => {"a": 42, "b": 2, "c": 3}

   Subtraction - -
       As  well  as normal arithmetic subtraction on numbers, the - operator can be used on arrays to remove all
       occurrences of the second array´s elements from the first array.

           jq ´4 - .a´
              {"a":3}
           => 1

           jq ´. - ["xml", "yaml"]´
              ["xml", "yaml", "json"]
           => ["json"]

   Multiplication, division, modulo - *, /, and %
       These infix operators behave as expected when given two numbers. Division by zero raises an error. x %  y
       computes x modulo y.

       Multiplying  a  string  by  a  number  produces the concatenation of that string that many times. "x" * 0
       produces null.

       Dividing a string by another splits the first using the second as separators.

       Multiplying two objects will merge them recursively: this works like addition but if both objects contain
       a value for the same key, and the values are objects, the two are merged with the same strategy.

           jq ´10 / . * 3´
              5
           => 6

           jq ´. / ", "´
              "a, b,c,d, e"
           => ["a","b,c,d","e"]

           jq ´{"k": {"a": 1, "b": 2}} * {"k": {"a": 0,"c": 3}}´
              null
           => {"k": {"a": 0, "b": 2, "c": 3}}

           jq ´.[] | (1 / .)?´
              [1,0,-1]
           => 1, -1

   length
       The builtin function length gets the length of various different types of value:

       •   The length of a string is the number of Unicode codepoints it contains (which will be the same as its
           JSON-encoded length in bytes if it´s pure ASCII).

       •   The length of an array is the number of elements.

       •   The length of an object is the number of key-value pairs.

       •   The length of null is zero.

           jq ´.[] | length´ [[1,2], "string", {"a":2}, null] => 2, 6, 1, 0

   keys, keys_unsorted
       The builtin function keys, when given an object, returns its keys in an array.

       The keys are sorted "alphabetically", by unicode codepoint  order.  This  is  not  an  order  that  makes
       particular  sense  in any particular language, but you can count on it being the same for any two objects
       with the same set of keys, regardless of locale settings.

       When keys is given an array, it returns the valid  indices  for  that  array:  the  integers  from  0  to
       length-1.

       The  keys_unsorted  function  is  just like keys, but if the input is an object then the keys will not be
       sorted, instead the keys will roughly be in insertion order.

           jq ´keys´
              {"abc": 1, "abcd": 2, "Foo": 3}
           => ["Foo", "abc", "abcd"]

           jq ´keys´
              [42,3,35]
           => [0,1,2]

   has(key)
       The builtin function has returns whether the input object has the given key, or the input  array  has  an
       element at the given index.

       has($key)  has  the  same  effect  as  checking  whether  $key is a member of the array returned by keys,
       although has will be faster.

           jq ´map(has("foo"))´
              [{"foo": 42}, {}]
           => [true, false]

           jq ´map(has(2))´
              [[0,1], ["a","b","c"]]
           => [false, true]

   in
       The builtin function in returns the input key is in the given object, or the input index  corresponds  to
       an element in the given array. It is, essentially, an inversed version of has.

           jq ´.[] | in({"foo": 42})´
              ["foo", "bar"]
           => true, false

           jq ´map(in([0,1]))´
              [2, 0]
           => [false, true]

   path(path_expression)
       Outputs  array representations of the given path expression in .. The outputs are arrays of strings (keys
       in objects0 and/or numbers (array indices.

       Path expressions are jq expressions like .a, but also .[]. There are two types of path expressions:  ones
       that  can  match  exactly,  and  ones that cannot. For example, .a.b.c is an exact match path expression,
       while .a[].b is not.

       path(exact_path_expression) will produce the array representation of the path expression even if it  does
       not exist in ., if . is null or an array or an object.

       path(pattern) will produce array representations of the paths matching pattern if the paths exist in ..

       Note   that   the   path   expressions   are  not  different  from  normal  expressions.  The  expression
       path(..|select(type=="boolean")) outputs all the paths to boolean values in ., and only those paths.

           jq ´path(.a[0].b)´
              null
           => ["a",0,"b"]

           jq ´[path(..)]´
              {"a":[{"b":1}]}
           => [[],["a"],["a",0],["a",0,"b"]]

   del(path_expression)
       The builtin function del removes a key and its corresponding value from an object.

           jq ´del(.foo)´
              {"foo": 42, "bar": 9001, "baz": 42}
           => {"bar": 9001, "baz": 42}

           jq ´del(.[1, 2])´
              ["foo", "bar", "baz"]
           => ["foo"]

   to_entries, from_entries, with_entries
       These functions convert between an object and an array of key-value pairs. If  to_entries  is  passed  an
       object, then for each k: v entry in the input, the output array includes {"key": k, "value": v}.

       from_entries does the opposite conversion, and with_entries(foo) is a shorthand for to_entries | map(foo)
       | from_entries, useful for doing some operation to all keys and values of an object. from_entries accepts
       key, Key, Name, value and Value as keys.

           jq ´to_entries´
              {"a": 1, "b": 2}
           => [{"key":"a", "value":1}, {"key":"b", "value":2}]

           jq ´from_entries´
              [{"key":"a", "value":1}, {"key":"b", "value":2}]
           => {"a": 1, "b": 2}

           jq ´with_entries(.key |= "KEY_" + .)´
              {"a": 1, "b": 2}
           => {"KEY_a": 1, "KEY_b": 2}

   select(boolean_expression)
       The function select(foo) produces its input unchanged if foo returns true for that input, and produces no
       output otherwise.

       It´s useful for filtering lists: [1,2,3] | map(select(. >= 2)) will give you [2,3].

           jq ´map(select(. >= 2))´
              [1,5,3,0,7]
           => [5,3,7]

           jq ´.[] | select(.id == "second")´
              [{"id": "first", "val": 1}, {"id": "second", "val": 2}]
           => {"id": "second", "val": 2}

   arrays, objects, iterables, booleans, numbers, normals, finites, strings, nulls, values, scalars
       These built-ins select only inputs that are arrays, objects, iterables  (arrays  or  objects),  booleans,
       numbers, normal numbers, finite numbers, strings, null, non-null values, and non-iterables, respectively.

           jq ´.[]|numbers´
              [[],{},1,"foo",null,true,false]
           => 1

   empty
       empty returns no results. None at all. Not even null.

       It´s useful on occasion. You´ll know if you need it :)

           jq ´1, empty, 2´
              null
           => 1, 2

           jq ´[1,2,empty,3]´
              null
           => [1,2,3]

   error(message)
       Produces  an  error, just like .a applied to values other than null and objects would, but with the given
       message as the error´s value.

   $__loc__
       Produces an object with a "file" key and a "line" key, with the filename and line number  where  $__loc__
       occurs, as values.

           jq ´try error("\($__loc__)") catch .´
              null
           => "{\"file\":\"<top-level>\",\"line\":1}"

   map(x), map_values(x)
       For  any  filter  x,  map(x)  will  run  that filter for each element of the input array, and produce the
       outputs a new array. map(.+1) will increment each element of an array of numbers.

       Similarly, map_values(x) will run that filter for each element, but it will  return  an  object  when  an
       object is passed.

       map(x) is equivalent to [.[] | x]. In fact, this is how it´s defined. Similarly, map_values(x) is defined
       as .[] |= x.

           jq ´map(.+1)´
              [1,2,3]
           => [2,3,4]

           jq ´map_values(.+1)´
              {"a": 1, "b": 2, "c": 3}
           => {"a": 2, "b": 3, "c": 4}

   paths, paths(node_filter), leaf_paths
       paths outputs the paths to all the elements in its input (except it  does  not  output  the  empty  list,
       representing . itself).

       paths(f)  outputs  the paths to any values for which f is true. That is, paths(numbers) outputs the paths
       to all numeric values.

       leaf_paths is an alias of paths(scalars); leaf_paths is deprecated and will be removed in the next  major
       release.

           jq ´[paths]´
              [1,[[],{"a":2}]]
           => [[0],[1],[1,0],[1,1],[1,1,"a"]]

           jq ´[paths(scalars)]´
              [1,[[],{"a":2}]]
           => [[0],[1,1,"a"]]

   add
       The  filter add takes as input an array, and produces as output the elements of the array added together.
       This might mean summed, concatenated or merged depending on the types of the elements of the input  array
       - the rules are the same as those for the + operator (described above).

       If the input is an empty array, add returns null.

           jq ´add´
              ["a","b","c"]
           => "abc"

           jq ´add´
              [1, 2, 3]
           => 6

           jq ´add´
              []
           => null

   any, any(condition), any(generator; condition)
       The  filter  any takes as input an array of boolean values, and produces true as output if any of the the
       elements of the array is true.

       If the input is an empty array, any returns false.

       The any(condition) form applies the given condition to the elements of the input array.

       The any(generator; condition) form applies the given condition to all the outputs of the given generator.

           jq ´any´
              [true, false]
           => true

           jq ´any´
              [false, false]
           => false

           jq ´any´
              []
           => false

   all, all(condition), all(generator; condition)
       The filter all takes as input an array of boolean values, and produces true as output if all of  the  the
       elements of the array are true.

       The all(condition) form applies the given condition to the elements of the input array.

       The all(generator; condition) form applies the given condition to all the outputs of the given generator.

       If the input is an empty array, all returns true.

           jq ´all´
              [true, false]
           => false

           jq ´all´
              [true, true]
           => true

           jq ´all´
              []
           => true

   [Requires 1.5] flatten, flatten(depth)
       The  filter  flatten  takes  as  input  an array of nested arrays, and produces a flat array in which all
       arrays inside the original array have been recursively replaced by their values. You can pass an argument
       to it to specify how many levels of nesting to flatten.

       flatten(2) is like flatten, but going only up to two levels deep.

           jq ´flatten´
              [1, [2], [[3]]]
           => [1, 2, 3]

           jq ´flatten(1)´
              [1, [2], [[3]]]
           => [1, 2, [3]]

           jq ´flatten´
              [[]]
           => []

           jq ´flatten´
              [{"foo": "bar"}, [{"foo": "baz"}]]
           => [{"foo": "bar"}, {"foo": "baz"}]

   range(upto), range(from;upto) range(from;upto;by)
       The  range function produces a range of numbers. range(4;10) produces 6 numbers, from 4 (inclusive) to 10
       (exclusive). The numbers are produced as separate outputs. Use [range(4;10)] to get a range as an array.

       The one argument form generates numbers from 0 to the given number, with an increment of 1.

       The two argument form generates numbers from from to upto with an increment of 1.

       The three argument form generates numbers from to upto with an increment of by.

           jq ´range(2;4)´
              null
           => 2, 3

           jq ´[range(2;4)]´
              null
           => [2,3]

           jq ´[range(4)]´
              null
           => [0,1,2,3]

           jq ´[range(0;10;3)]´
              null
           => [0,3,6,9]

           jq ´[range(0;10;-1)]´
              null
           => []

           jq ´[range(0;-5;-1)]´
              null
           => [0,-1,-2,-3,-4]

   floor
       The floor function returns the floor of its numeric input.

           jq ´floor´
              3.14159
           => 3

   sqrt
       The sqrt function returns the square root of its numeric input.

           jq ´sqrt´
              9
           => 3

   tonumber
       The tonumber function parses its input as a number. It will convert correctly-formatted strings to  their
       numeric equivalent, leave numbers alone, and give an error on all other input.

           jq ´.[] | tonumber´
              [1, "1"]
           => 1, 1

   tostring
       The  tostring function prints its input as a string. Strings are left unchanged, and all other values are
       JSON-encoded.

           jq ´.[] | tostring´
              [1, "1", [1]]
           => "1", "1", "[1]"

   type
       The type function returns the type of its argument as a string, which is one of  null,  boolean,  number,
       string, array or object.

           jq ´map(type)´
              [0, false, [], {}, null, "hello"]
           => ["number", "boolean", "array", "object", "null", "string"]

   infinite, nan, isinfinite, isnan, isfinite, isnormal
       Some  arithmetic  operations can yield infinities and "not a number" (NaN) values. The isinfinite builtin
       returns true if its input is infinite. The isnan builtin returns true if its input is a NaN. The infinite
       builtin  returns  a  positive infinite value. The nan builtin returns a NaN. The isnormal builtin returns
       true if its input is a normal number.

       Note that division by zero raises an error.

       Currently most arithmetic operations operating on infinities, NaNs, and sub-normals do not raise errors.

           jq ´.[] | (infinite * .) < 0´
              [-1, 1]
           => true, false

           jq ´infinite, nan | type´
              null
           => "number", "number"

   sort, sort_by(path_expression)
       The sort functions sorts its input, which must be an array. Values are sorted in the following order:

       •   nullfalsetrue

       •   numbers

       •   strings, in alphabetical order (by unicode codepoint value)

       •   arrays, in lexical order

       •   objects

       The ordering for objects is a little complex: first they´re compared by comparing their sets of keys  (as
       arrays in sorted order), and if their keys are equal then the values are compared key by key.

       sort may be used to sort by a particular field of an object, or by applying any jq filter.

       sort_by(foo) compares two elements by comparing the result of foo on each element.

           jq ´sort´
              [8,3,null,6]
           => [null,3,6,8]

           jq ´sort_by(.foo)´
              [{"foo":4, "bar":10}, {"foo":3, "bar":100}, {"foo":2, "bar":1}]
           => [{"foo":2, "bar":1}, {"foo":3, "bar":100}, {"foo":4, "bar":10}]

   group_by(path_expression)
       group_by(.foo)  takes  as  input  an  array, groups the elements having the same .foo field into separate
       arrays, and produces all of these arrays as elements of a larger array, sorted by the value of  the  .foo
       field.

       Any  jq  expression, not just a field access, may be used in place of .foo. The sorting order is the same
       as described in the sort function above.

           jq ´group_by(.foo)´
              [{"foo":1, "bar":10}, {"foo":3, "bar":100}, {"foo":1, "bar":1}]
           => [[{"foo":1, "bar":10}, {"foo":1, "bar":1}], [{"foo":3, "bar":100}]]

   min, max, min_by(path_exp), max_by(path_exp)
       Find the minimum or maximum element of the input array.

       The min_by(path_exp) and max_by(path_exp) functions allow you to specify a particular field  or  property
       to examine, e.g. min_by(.foo) finds the object with the smallest foo field.

           jq ´min´
              [5,4,2,7]
           => 2

           jq ´max_by(.foo)´
              [{"foo":1, "bar":14}, {"foo":2, "bar":3}]
           => {"foo":2, "bar":3}

   unique, unique_by(path_exp)
       The  unique function takes as input an array and produces an array of the same elements, in sorted order,
       with duplicates removed.

       The unique_by(path_exp) function will keep only one element for  each  value  obtained  by  applying  the
       argument. Think of it as making an array by taking one element out of every group produced by group.

           jq ´unique´
              [1,2,5,3,5,3,1,3]
           => [1,2,3,5]

           jq ´unique_by(.foo)´
              [{"foo": 1, "bar": 2}, {"foo": 1, "bar": 3}, {"foo": 4, "bar": 5}]
           => [{"foo": 1, "bar": 2}, {"foo": 4, "bar": 5}]

           jq ´unique_by(length)´
              ["chunky", "bacon", "kitten", "cicada", "asparagus"]
           => ["bacon", "chunky", "asparagus"]

   reverse
       This function reverses an array.

           jq ´reverse´
              [1,2,3,4]
           => [4,3,2,1]

   contains(element)
       The  filter  contains(b)  will  produce true if b is completely contained within the input. A string B is
       contained in a string A if B is a substring of A. An array B is contained in an array A if  all  elements
       in  B  are  contained in any element in A. An object B is contained in object A if all of the values in B
       are contained in the value in A with the same key. All other types are assumed to be  contained  in  each
       other if they are equal.

           jq ´contains("bar")´
              "foobar"
           => true

           jq ´contains(["baz", "bar"])´
              ["foobar", "foobaz", "blarp"]
           => true

           jq ´contains(["bazzzzz", "bar"])´
              ["foobar", "foobaz", "blarp"]
           => false

           jq ´contains({foo: 12, bar: [{barp: 12}]})´
              {"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]}
           => true

           jq ´contains({foo: 12, bar: [{barp: 15}]})´
              {"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]}
           => false

   indices(s)
       Outputs  an array containing the indices in . where s occurs. The input may be an array, in which case if
       s is an array then the indices output will be those where all elements in . match those of s.

           jq ´indices(", ")´
              "a,b, cd, efg, hijk"
           => [3,7,12]

           jq ´indices(1)´
              [0,1,2,1,3,1,4]
           => [1,3,5]

           jq ´indices([1,2])´
              [0,1,2,3,1,4,2,5,1,2,6,7]
           => [1,8]

   index(s), rindex(s)
       Outputs the index of the first (index) or last (rindex) occurrence of s in the input.

           jq ´index(", ")´
              "a,b, cd, efg, hijk"
           => 3

           jq ´rindex(", ")´
              "a,b, cd, efg, hijk"
           => 12

   inside
       The filter inside(b) will produce true if the input is completely contained within b. It is, essentially,
       an inversed version of contains.

           jq ´inside("foobar")´
              "bar"
           => true

           jq ´inside(["foobar", "foobaz", "blarp"])´
              ["baz", "bar"]
           => true

           jq ´inside(["foobar", "foobaz", "blarp"])´
              ["bazzzzz", "bar"]
           => false

           jq ´inside({"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]})´
              {"foo": 12, "bar": [{"barp": 12}]}
           => true

           jq ´inside({"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]})´
              {"foo": 12, "bar": [{"barp": 15}]}
           => false

   startswith(str)
       Outputs true if . starts with the given string argument.

           jq ´[.[]|startswith("foo")]´
              ["fo", "foo", "barfoo", "foobar", "barfoob"]
           => [false, true, false, true, false]

   endswith(str)
       Outputs true if . ends with the given string argument.

           jq ´[.[]|endswith("foo")]´
              ["foobar", "barfoo"]
           => [false, true]

   combinations, combinations(n)
       Outputs  all  combinations  of  the elements of the arrays in the input array. If given an argument n, it
       outputs all combinations of n repetitions of the input array.

           jq ´combinations´
              [[1,2], [3, 4]]
           => [1, 3], [1, 4], [2, 3], [2, 4]

           jq ´combinations(2)´
              [0, 1]
           => [0, 0], [0, 1], [1, 0], [1, 1]

   ltrimstr(str)
       Outputs its input with the given prefix string removed, if it starts with it.

           jq ´[.[]|ltrimstr("foo")]´
              ["fo", "foo", "barfoo", "foobar", "afoo"]
           => ["fo","","barfoo","bar","afoo"]

   rtrimstr(str)
       Outputs its input with the given suffix string removed, if it ends with it.

           jq ´[.[]|rtrimstr("foo")]´
              ["fo", "foo", "barfoo", "foobar", "foob"]
           => ["fo","","bar","foobar","foob"]

   explode
       Converts an input string into an array of the string´s codepoint numbers.

           jq ´explode´
              "foobar"
           => [102,111,111,98,97,114]

   implode
       The inverse of explode.

           jq ´implode´
              [65, 66, 67]
           => "ABC"

   split
       Splits an input string on the separator argument.

           jq ´split(", ")´
              "a, b,c,d, e, "
           => ["a","b,c,d","e",""]

   join(str)
       Joins the array of elements given as input, using the argument as separator. It is the inverse of  split:
       that is, running split("foo") | join("foo") over any input string returns said input string.

           jq ´join(", ")´
              ["a","b,c,d","e"]
           => "a, b,c,d, e"

   ascii_downcase, ascii_upcase
       Emit  a  copy of the input string with its alphabetic characters (a-z and A-Z) converted to the specified
       case.

   while(cond; update)
       The while(cond; update) function allows you to repeatedly apply an update to . until cond is false.

       Note that while(cond; update) is internally defined as a recursive jq function.  Recursive  calls  within
       while  will  not  consume  additional  memory  if  update produces at most one output for each input. See
       advanced topics below.

           jq ´[while(.<100; .*2)]´
              1
           => [1,2,4,8,16,32,64]

   until(cond; next)
       The until(cond; next) function allows you to repeatedly apply the expression next, initially to . then to
       its  own output, until cond is true. For example, this can be used to implement a factorial function (see
       below).

       Note that until(cond; next) is internally defined as a recursive  jq  function.  Recursive  calls  within
       until()  will  not  consume  additional  memory  if  next produces at most one output for each input. See
       advanced topics below.

           jq ´[.,1]|until(.[0] < 1; [.[0] - 1, .[1] * .[0]])|.[1]´
              4
           => 24

   recurse(f), recurse, recurse(f; condition), recurse_down
       The recurse(f) function allows you to search through a recursive structure, and extract interesting  data
       from all levels. Suppose your input represents a filesystem:

           {"name": "/", "children": [
             {"name": "/bin", "children": [
               {"name": "/bin/ls", "children": []},
               {"name": "/bin/sh", "children": []}]},
             {"name": "/home", "children": [
               {"name": "/home/stephen", "children": [
                 {"name": "/home/stephen/jq", "children": []}]}]}]}

       Now   suppose  you  want  to  extract  all  of  the  filenames  present.  You  need  to  retrieve  .name,
       .children[].name, .children[].children[].name, and so on. You can do this with:

           recurse(.children[]) | .name

       When called without an argument, recurse is equivalent to recurse(.[]?).

       recurse(f) is identical to recurse(f; . != null) and can be used without concerns about recursion depth.

       recurse(f; condition) is a generator which begins by emitting .  and  then  emits  in  turn  .|f,  .|f|f,
       .|f|f|f,  ...  so  long  as  the computed value satisfies the condition. For example, to generate all the
       integers, at least in principle, one could write recurse(.+1; true).

       For legacy reasons, recurse_down exists as an alias to calling recurse without arguments. This  alias  is
       considered deprecated and will be removed in the next major release.

       The  recursive  calls  in recurse will not consume additional memory whenever f produces at most a single
       output for each input.

           jq ´recurse(.foo[])´
              {"foo":[{"foo": []}, {"foo":[{"foo":[]}]}]}
           => {"foo":[{"foo":[]},{"foo":[{"foo":[]}]}]}, {"foo":[]}, {"foo":[{"foo":[]}]}, {"foo":[]}

           jq ´recurse´
              {"a":0,"b":[1]}
           => {"a":0,"b":[1]}, 0, [1], 1

           jq ´recurse(. * .; . < 20)´
              2
           => 2, 4, 16

   ..
       Short-hand for recurse without arguments. This is intended to resemble the XPath // operator.  Note  that
       ..a  does not work; use ..|a instead. In the example below we use ..|.a? to find all the values of object
       keys "a" in any object found "below" ..

           jq ´..|.a?´
              [[{"a":1}]]
           => 1

   env
       Outputs an object representing jq´s environment.

           jq ´env.PAGER´
              null
           => "less"

   transpose
       Transpose a possibly jagged matrix (an array of arrays). Rows are padded with  nulls  so  the  result  is
       always rectangular.

           jq ´transpose´
              [[1], [2,3]]
           => [[1,2],[null,3]]

   bsearch(x)
       bsearch(x) conducts a binary search for x in the input array. If the input is sorted and contains x, then
       bsearch(x) will return its index in the array; otherwise, if the array is sorted, it will  return  (-1  -
       ix)  where ix is an insertion point such that the array would still be sorted after the insertion of x at
       ix. If the array is not sorted, bsearch(x) will return an integer that is probably of no interest.

           jq ´bsearch(0)´
              [0,1]
           => 0

           jq ´bsearch(0)´
              [1,2,3]
           => -1

           jq ´bsearch(4) as $ix | if $ix < 0 then .[-(1+$ix)] = 4 else . end´
              [1,2,3]
           => [1,2,3,4]

   String interpolation - \(foo)
       Inside a string, you can put an expression inside parens  after  a  backslash.  Whatever  the  expression
       returns will be interpolated into the string.

           jq ´"The input was \(.), which is one less than \(.+1)"´
              42
           => "The input was 42, which is one less than 43"

   Convert to/from JSON
       The tojson and fromjson builtins dump values as JSON texts or parse JSON texts into values, respectively.
       The tojson builtin differs from tostring in  that  tostring  returns  strings  unmodified,  while  tojson
       encodes strings as JSON strings.

           jq ´[.[]|tostring]´
              [1, "foo", ["foo"]]
           => ["1","foo","[\"foo\"]"]

           jq ´[.[]|tojson]´
              [1, "foo", ["foo"]]
           => ["1","\"foo\"","[\"foo\"]"]

           jq ´[.[]|tojson|fromjson]´
              [1, "foo", ["foo"]]
           => [1,"foo",["foo"]]

   Format strings and escaping
       The  @foo  syntax is used to format and escape strings, which is useful for building URLs, documents in a
       language like HTML or XML, and so forth. @foo can be used as a filter on its own, the possible  escapings
       are:

       @text:

              Calls tostring, see that function for details.

       @json:

              Serializes the input as JSON.

       @html:

              Applies HTML/XML escaping, by mapping the characters <>&´" to their entity equivalents &lt;, &gt;,
              &amp;, &apos;, &quot;.

       @uri:

              Applies percent-encoding, by mapping all reserved URI characters to a %XX sequence.

       @csv:

              The input must be an array, and it is rendered as CSV with double quotes for strings,  and  quotes
              escaped by repetition.

       @tsv:

              The  input  must  be  an array, and it is rendered as TSV (tab-separated values). Each input array
              will be printed as a single line. Fields are  separated  by  a  single  tab  (ascii  0x09).  Input
              characters  line-feed  (ascii  0x0a), carriage-return (ascii 0x0d), tab (ascii 0x09) and backslash
              (ascii 0x5c) will be output as escape sequences \n, \r, \t, \\ respectively.

       @sh:

              The input is escaped suitable for use in a command-line for a POSIX shell.  If  the  input  is  an
              array, the output will be a series of space-separated strings.

       @base64:

              The input is converted to base64 as specified by RFC 4648.

       This syntax can be combined with string interpolation in a useful way. You can follow a @foo token with a
       string literal. The contents of the string literal will not be escaped. However, all interpolations  made
       inside that string literal will be escaped. For instance,

           @uri "https://www.google.com/search?q=\(.search)"

       will produce the following output for the input {"search":"what is jq?"}:

           "https://www.google.com/search?q=what%20is%20jq%3F"

       Note  that  the  slashes, question mark, etc. in the URL are not escaped, as they were part of the string
       literal.

           jq ´@html´
              "This works if x < y"
           => "This works if x &lt; y"

           jq ´@sh "echo \(.)"´
              "O´Hara´s Ale"
           => "echo ´O´\\´´Hara´\\´´s Ale´"

   Dates
       jq provides some basic date handling functionality, with some high-level and low-level builtins.  In  all
       cases these builtins deal exclusively with time in UTC.

       The fromdateiso8601 builtin parses datetimes in the ISO 8601 format to a number of seconds since the Unix
       epoch (1970-01-01T00:00:00Z). The todateiso8601 builtin does the inverse.

       The fromdate builtin parses datetime strings. Currently fromdate only supports ISO 8601 datetime strings,
       but in the future it will attempt to parse datetime strings in more formats.

       The todate builtin is an alias for todateiso8601.

       The now builtin outputs the current time, in seconds since the Unix epoch.

       Low-level  jq  interfaces  to the C-library time functions are also provided: strptime, strftime, mktime,
       and gmtime. Refer to your host operating system´s documentation for the format strings used  by  strptime
       and  strftime.  Note:  these  are  not  necessarily  stable  interfaces  in  jq, particularly as to their
       localization functionality.

       The gmtime builtin consumes a number of seconds since the Unix epoch and outputs  a  "broken  down  time"
       representation  of  time  as  an  array  of  numbers  representing  (in  this order): the year, the month
       (zero-based), the day of the month, the hour of the day, the minute  of  the  hour,  the  second  of  the
       minute, the day of the week, and the day of the year -- all one-based unless otherwise stated.

       The mktime builtin consumes "broken down time" representations of time output by gmtime and strptime.

       The  strptime(fmt)  builtin  parses input strings matching the fmt argument. The output is in the "broken
       down time" representation consumed by gmtime and output by mktime.

       The strftime(fmt) builtin formats a time with the given format.

       The format strings for strptime and strftime are described in typical C library documentation. The format
       string for ISO 8601 datetime is "%Y-%m-%dT%H:%M:%SZ".

       jq may not support some or all of this date functionality on some systems.

           jq ´fromdate´
              "2015-03-05T23:51:47Z"
           => 1425599507

           jq ´strptime("%Y-%m-%dT%H:%M:%SZ")´
              "2015-03-05T23:51:47Z"
           => [2015,2,5,23,51,47,4,63]

           jq ´strptime("%Y-%m-%dT%H:%M:%SZ")|mktime´
              "2015-03-05T23:51:47Z"
           => 1425599507

CONDITIONALS AND COMPARISONS

   ==, !=
       The  expression  ´a  ==  b´  will  produce  ´true´  if  the result of a and b are equal (that is, if they
       represent equivalent JSON documents) and ´false´ otherwise. In particular, strings are  never  considered
       equal to numbers. If you´re coming from Javascript, jq´s == is like Javascript´s === - considering values
       equal only when they have the same type as well as the same value.

       != is "not equal", and ´a != b´ returns the opposite value of ´a == b´

           jq ´.[] == 1´
              [1, 1.0, "1", "banana"]
           => true, true, false, false

   if-then-else
       if A then B else C end will act the same as B if A produces a value other than false or null, but act the
       same as C otherwise.

       Checking for false or null is a simpler notion of "truthiness" than is found in Javascript or Python, but
       it means that you´ll sometimes have to be more explicit about the condition  you  want:  you  can´t  test
       whether,  e.g.  a  string  is  empty using if .name then A else B end, you´ll need something more like if
       (.name | length) > 0 then A else B end instead.

       If the condition A produces multiple results, it is considered "true" if any  of  those  results  is  not
       false or null. If it produces zero results, it´s considered false.

       More cases can be added to an if using elif A then B syntax.

           jq ´if . == 0 then

       "zero" elif . == 1 then "one" else "many" end´ 2 => "many"

   >, >=, <=, <
       The comparison operators >, >=, <=, < return whether their left argument is greater than, greater than or
       equal to, less than or equal to or less than their right argument (respectively).

       The ordering is the same as that described for sort, above.

           jq ´. < 5´
              2
           => true

   and/or/not
       jq supports the normal Boolean operators  and/or/not.  They  have  the  same  standard  of  truth  as  if
       expressions - false and null are considered "false values", and anything else is a "true value".

       If  an  operand  of  one of these operators produces multiple results, the operator itself will produce a
       result for each input.

       not is in fact a builtin function rather than an operator, so it is called as a filter  to  which  things
       can be piped rather than with special syntax, as in .foo and .bar | not.

       These  three  only  produce  the  values  "true"  and "false", and so are only useful for genuine Boolean
       operations, rather than the common Perl/Python/Ruby idiom of "value_that_may_be_null or default". If  you
       want  to  use  this  form of "or", picking between two values rather than evaluating a condition, see the
       "//" operator below.

           jq ´42 and "a string"´
              null
           => true

           jq ´(true, false) or false´
              null
           => true, false

           jq ´(true, true) and (true, false)´
              null
           => true, false, true, false

           jq ´[true, false | not]´
              null
           => [false, true]

   Alternative operator - //
       A filter of the form a // b produces the same results as a, if a produces results other  than  false  and
       null. Otherwise, a // b produces the same results as b.

       This  is  useful  for  providing defaults: .foo // 1 will evaluate to 1 if there´s no .foo element in the
       input. It´s similar to how or is sometimes used in Python (jq´s or  operator  is  reserved  for  strictly
       Boolean operations).

           jq ´.foo // 42´
              {"foo": 19}
           => 19

           jq ´.foo // 42´
              {}
           => 42

   try-catch
       Errors  can  be caught by using try EXP catch EXP. The first expression is executed, and if it fails then
       the second is executed with the error message. The output of the handler, if any, is output as if it  had
       been the output of the expression to try.

       The try EXP form uses empty as the exception handler.

           jq ´try .a catch ". is not an object"´
              true
           => ". is not an object"

           jq ´[.[]|try .a]´
              [{}, true, {"a":1}]
           => [null, 1]

           jq ´try error("some exception") catch .´
              true
           => "some exception"

   Breaking out of control structures
       A  convenient  use of try/catch is to break out of control structures like reduce, foreach, while, and so
       on.

       For example:

           # Repeat an expression until it raises "break" as an
           # error, then stop repeating without re-raising the error.
           # But if the error caught is not "break" then re-raise it.
           try repeat(exp) catch .=="break" then empty else error;

       jq has a syntax for named lexical labels to "break" or "go (back) to":

           label $out | ... break $out ...

       The break $label_name expression will cause the program to to act as though the  nearest  (to  the  left)
       label $label_name produced empty.

       The relationship between the break and corresponding label is lexical: the label has to be "visible" from
       the break.

       To break out of a reduce, for example:

           label $out | reduce .[] as $item (null; if .==false then break $out else ... end)

       The following jq program produces a syntax error:

           break $out

       because no label $out is visible.

   ? operator
       The ? operator, used as EXP?, is shorthand for try EXP.

           jq ´[.[]|(.a)?]´
              [{}, true, {"a":1}]
           => [null, 1]

REGULAR EXPRESSIONS (PCRE)

       jq uses the Oniguruma regular expression library, as do php, ruby, TextMate, Sublime Text,  etc,  so  the
       description here will focus on jq specifics.

       The jq regex filters are defined so that they can be used using one of these patterns:

           STRING | FILTER( REGEX )
           STRING | FILTER( REGEX; FLAGS )
           STRING | FILTER( [REGEX] )
           STRING | FILTER( [REGEX, FLAGS] )

       where:  *  STRING,  REGEX and FLAGS are jq strings and subject to jq string interpolation; * REGEX, after
       string interpolation, should be a valid PCRE regex; * FILTER is  one  of  test,  match,  or  capture,  as
       described below.

       FLAGS is a string consisting of one of more of the supported flags:

       •   g - Global search (find all matches, not just the first)

       •   i - Case insensitive search

       •   m - Multi line mode (´.´ will match newlines)

       •   n - Ignore empty matches

       •   p - Both s and m modes are enabled

       •   s - Single line mode (´^´ -> ´\A´, ´$´ -> ´\Z´)

       •   l - Find longest possible matches

       •   x - Extended regex format (ignore whitespace and comments)

       To match whitespace in an x pattern use an escape such as \s, e.g.

       •   test( "a\sb", "x" ).

       Note that certain flags may also be specified within REGEX, e.g.

       •   jq -n ´("test", "TEst", "teST", "TEST") | test( "(?i)te(?-i)st" )´

       evaluates to: true, true, false, false.

   [Requires 1.5] test(val), test(regex; flags)
       Like  match,  but  does not return match objects, only true or false for whether or not the regex matches
       the input.

           jq ´test("foo")´
              "foo"
           => true

           jq ´.[] | test("a b c # spaces are ignored"; "ix")´
              ["xabcd", "ABC"]
           => true, true

   [Requires 1.5] match(val), match(regex; flags)
       match outputs an object for each match it finds. Matches have the following fields:

       •   offset - offset in UTF-8 codepoints from the beginning of the input

       •   length - length in UTF-8 codepoints of the match

       •   string - the string that it matched

       •   captures - an array of objects representing capturing groups.

       Capturing group objects have the following fields:

       •   offset - offset in UTF-8 codepoints from the beginning of the input

       •   length - length in UTF-8 codepoints of this capturing group

       •   string - the string that was captured

       •   name - the name of the capturing group (or null if it was unnamed)

       Capturing groups that did not match anything return an offset of -1

           jq ´match("(abc)+"; "g")´
              "abc abc"
           => {"offset": 0, "length": 3, "string": "abc", "captures": [{"offset": 0, "length": 3, "string": "abc", "name": null}]}, {"offset": 4, "length": 3, "string": "abc", "captures": [{"offset": 4, "length": 3, "string": "abc", "name": null}]}

           jq ´match("foo")´
              "foo bar foo"
           => {"offset": 0, "length": 3, "string": "foo", "captures": []}

           jq ´match(["foo", "ig"])´
              "foo bar FOO"
           => {"offset": 0, "length": 3, "string": "foo", "captures": []}, {"offset": 8, "length": 3, "string": "FOO", "captures": []}

           jq ´match("foo (?<bar123>bar)? foo"; "ig")´
              "foo bar foo foo  foo"
           => {"offset": 0, "length": 11, "string": "foo bar foo", "captures": [{"offset": 4, "length": 3, "string": "bar", "name": "bar123"}]}, {"offset": 12, "length": 8, "string": "foo  foo", "captures": [{"offset": -1, "length": 0, "string": null, "name": "bar123"}]}

           jq ´[ match("."; "g")] | length´
              "abc"
           => 3

   [Requires 1.5] capture(val), capture(regex; flags)
       Collects the named captures in a JSON object, with the name of each capture as the key, and  the  matched
       string as the corresponding value.

           jq ´capture("(?<a>[a-z]+)-(?<n>[0-9]+)")´
              "xyzzy-14"
           => { "a": "xyzzy", "n": "14" }

   [Requires 1.5] scan(regex), scan(regex; flags)
       Emit  a stream of the non-overlapping substrings of the input that match the regex in accordance with the
       flags, if any have been specified. If there is no match, the stream is empty. To capture all the  matches
       for each input string, use the idiom [ expr ], e.g. [ scan(regex) ].

   split(regex; flags)
       For backwards compatibility, split splits on a string, not a regex.

   [Requires 1.5] splits(regex), splits(regex; flags)
       These provide the same results as their split counterparts, but as a stream instead of an array.

   [Requires 1.5] sub(regex; tostring) sub(regex; string; flags)
       Emit  the  string obtained by replacing the first match of regex in the input string with tostring, after
       interpolation. tostring should be a jq string, and may contain references to named  captures.  The  named
       captures  are,  in  effect,  presented  as  a  JSON  object (as constructed by capture) to tostring, so a
       reference to a captured variable named "x" would take the form: "(.x)".

   [Requires 1.5] gsub(regex; string), gsub(regex; string; flags)
       gsub is like sub but all the non-overlapping occurrences of the regex are replaced by the  string,  after
       interpolation.

ADVANCED FEATURES

       Variables  are an absolute necessity in most programming languages, but they´re relegated to an "advanced
       feature" in jq.

       In most languages, variables are the only means of passing around data. If you calculate a value, and you
       want  to use it more than once, you´ll need to store it in a variable. To pass a value to another part of
       the program, you´ll need that part of the program to define a variable (as a function  parameter,  object
       member, or whatever) in which to place the data.

       It  is  also  possible  to  define  functions  in  jq, although this is is a feature whose biggest use is
       defining jq´s standard library (many jq functions such as map and find are in fact written in jq).

       jq has reduction operators, which are very powerful but a  bit  tricky.  Again,  these  are  mostly  used
       internally, to define some useful bits of jq´s standard library.

       It  may not be obvious at first, but jq is all about generators (yes, as often found in other languages).
       Some utilities are provided to help deal with generators.

       Some minimal I/O support (besides reading JSON from standard input, and writing JSON to standard  output)
       is available.

       Finally, there is a module/library system.

   Variables
       In  jq, all filters have an input and an output, so manual plumbing is not necessary to pass a value from
       one part of a program to the next. Many expressions, for instance a + b, pass their input to two distinct
       subexpressions  (here  a  and b are both passed the same input), so variables aren´t usually necessary in
       order to use a value twice.

       For instance, calculating the average value of an array of numbers  requires  a  few  variables  in  most
       languages  -  at  least one to hold the array, perhaps one for each element or for a loop counter. In jq,
       it´s simply add / length - the add expression is given the array and produces its  sum,  and  the  length
       expression is given the array and produces its length.

       So,  there´s  generally  a  cleaner  way  to  solve  most  problems in jq than defining variables. Still,
       sometimes they do make things easier, so jq lets you define variables using expression as $variable.  All
       variable names start with $. Here´s a slightly uglier version of the array-averaging example:

           length as $array_length | add / $array_length

       We´ll  need a more complicated problem to find a situation where using variables actually makes our lives
       easier.

       Suppose we have an array of blog posts, with "author" and "title" fields, and  another  object  which  is
       used to map author usernames to real names. Our input looks like:

           {"posts": [{"title": "Frist psot", "author": "anon"},
                      {"title": "A well-written article", "author": "person1"}],
            "realnames": {"anon": "Anonymous Coward",
                          "person1": "Person McPherson"}}

       We want to produce the posts with the author field containing a real name, as in:

           {"title": "Frist psot", "author": "Anonymous Coward"}
           {"title": "A well-written article", "author": "Person McPherson"}

       We  use  a variable, $names, to store the realnames object, so that we can refer to it later when looking
       up author usernames:

           .realnames as $names | .posts[] | {title, author: $names[.author]}

       The expression exp as $x | ... means: for each value of expression exp, run the rest of the pipeline with
       the  entire  original  input,  and with $x set to that value. Thus as functions as something of a foreach
       loop.

       Just as {foo} is a handy way of writing {foo: .foo}, so {$foo} is a handy way of writing {foo:$foo}.

       Multiple variables may be declared using a single as expression by providing a pattern that  matches  the
       structure of the input (this is known as "destructuring"):

           . as {realnames: $names, posts: [$first, $second]} | ...

       The  variable  declarations  in array patterns (e.g., . as [$first, $second]) bind to the elements of the
       array in from the element at index zero on up, in order. When there is no value at the index for an array
       pattern element, null is bound to that variable.

       Variables are scoped over the rest of the expression that defines them, so

           .realnames as $names | (.posts[] | {title, author: $names[.author]})

       will work, but

           (.realnames as $names | .posts[]) | {title, author: $names[.author]}

       won´t.

       For  programming  language  theorists,  it´s  more accurate to say that jq variables are lexically-scoped
       bindings. In particular there´s no way to change the value of a binding; one can only setup a new binding
       with the same name, but which will not be visible where the old one was.

           jq ´.bar as $x | .foo | . + $x´
              {"foo":10, "bar":200}
           => 210

           jq ´. as $i|[(.*2|. as $i| $i), $i]´
              5
           => [10,5]

           jq ´. as [$a, $b, {c: $c}] | $a + $b + $c´
              [2, 3, {"c": 4, "d": 5}]
           => 9

           jq ´.[] as [$a, $b] | {a: $a, b: $b}´
              [[0], [0, 1], [2, 1, 0]]
           => {"a":0,"b":null}, {"a":0,"b":1}, {"a":2,"b":1}

   Defining Functions
       You can give a filter a name using "def" syntax:

           def increment: . + 1;

       From  then on, increment is usable as a filter just like a builtin function (in fact, this is how some of
       the builtins are defined). A function may take arguments:

           def map(f): [.[] | f];

       Arguments are passed as filters, not as values. The same argument may be referenced multiple  times  with
       different  inputs  (here f is run for each element of the input array). Arguments to a function work more
       like callbacks than like value arguments. This is important to understand. Consider:

           def foo(f): f|f;
           5|foo(.*2)

       The result will be 20 because f is .*2, and during the first invocation of f . will be 5, and the  second
       time  it will be 10 (5 * 2), so the result will be 20. Function arguments are filters, and filters expect
       an input when invoked.

       If you want the value-argument behaviour for defining simple functions, you can just use a variable:

           def addvalue(f): f as $f | map(. + $f);

       Or use the short-hand:

           def addvalue($f): ...;

       With either definition, addvalue(.foo) will add the current input´s .foo field to  each  element  of  the
       array.

       Multiple  definitions  using the same function name are allowed. Each re-definition replaces the previous
       one for the same number of function arguments, but only for references from functions (or  main  program)
       subsequent to the re-definition.

           jq ´def addvalue(f): . + [f]; map(addvalue(.[0]))´
              [[1,2],[10,20]]
           => [[1,2,1], [10,20,10]]

           jq ´def addvalue(f): f as $x | map(. + $x); addvalue(.[0])´
              [[1,2],[10,20]]
           => [[1,2,1,2], [10,20,1,2]]

   Reduce
       The  reduce  syntax  in jq allows you to combine all of the results of an expression by accumulating them
       into a single answer. As an example, we´ll pass [3,2,1] to this expression:

           reduce .[] as $item (0; . + $item)

       For each result that .[] produces, . + $item is run to accumulate a running total, starting  from  0.  In
       this  example,  .[]  produces the results 3, 2, and 1, so the effect is similar to running something like
       this:

           0 | (3 as $item | . + $item) |
               (2 as $item | . + $item) |
               (1 as $item | . + $item)

           jq ´reduce .[] as $item (0; . + $item)´
              [10,2,5,3]
           => 20

   limit(n; exp)
       The limit function extracts up to n outputs from exp.

           jq ´[limit(3;.[])]´
              [0,1,2,3,4,5,6,7,8,9]
           => [0,1,2]

   first(expr), last(expr), nth(n; expr)
       The first(expr) and last(expr) functions extract the first and last values from expr, respectively.

       The nth(n; expr) function extracts the nth value output by expr. This can be defined as def nth(n; expr):
       last(limit(n + 1; expr));. Note that nth(n; expr) doesn´t support negative values of n.

           jq ´[first(range(.)), last(range(.)), nth(./2; range(.))]´
              10
           => [0,9,5]

   first, last, nth(n)
       The first and last functions extract the first and last values from any array at ..

       The nth(n) function extracts the nth value of any array at ..

           jq ´[range(.)]|[first, last, nth(5)]´
              10
           => [0,9,5]

   foreach
       The  foreach  syntax  is  similar to reduce, but intended to allow the construction of limit and reducers
       that produce intermediate results (see example).

       The form is foreach EXP as $var (INIT; UPDATE; EXTRACT). Like reduce, INIT is evaluated once to produce a
       state  value,  then  each output of EXP is bound to $var, UPDATE is evaluated for each output of EXP with
       the current state and with $var visible. Each  value  output  by  UPDATE  replaces  the  previous  state.
       Finally, EXTRACT is evaluated for each new state to extract an output of foreach.

       This  is  mostly  useful  only  for  constructing  reduce-  and limit-like functions. But it is much more
       general, as it allows for partial reductions (see the example below).

           jq ´[foreach .[] as $item ([[],[]]; if $item == null then [[],.[0]] else [(.[0] + [$item]),[]] end; if $item == null then .[1] else empty end)]´
              [1,2,3,4,null,"a","b",null]
           => [[1,2,3,4],["a","b"]]

   Recursion
       As described above, recurse uses recursion, and any jq function can be recursive. The  while  builtin  is
       also implemented in terms of recursion.

       Tail  calls  are  optimized  whenever  the  expression to the left of the recursive call outputs its last
       value. In practice this means that the expression to the left of the recursive call  should  not  produce
       more than one output for each input.

       For example:

           def recurse(f): def r: ., (f | select(. != null) | r); r;

           def while(cond; update):
             def _while:
               if cond then ., (update | _while) else empty end;
             _while;

           def repeat(exp):
             def _repeat:
               exp, _repeat;
             _repeat;

   Generators and iterators
       Some  jq  operators  and  functions  are  actually generators in that they can produce zero, one, or more
       values for each input, just as one might expect in other programming languages that have generators.  For
       example,  .[]  generates  all the values in its input (which must be an array or an object), range(0; 10)
       generates the integers between 0 and 10, and so on.

       Even the comma operator is a generator, generating first the values generated by the  expression  to  the
       left  of  the  comma,  then  for each of those, the values generate by the expression on the right of the
       comma.

       The empty builtin is the generator that produces zero  outputs.  The  empty  builtin  backtracks  to  the
       preceding generator expression.

       All  jq  functions  can be generators just by using builtin generators. It is also possible to define new
       generators using only recursion and the comma  operator.  If  the  recursive  call(s)  is(are)  "in  tail
       position"  then  the  generator  will  be efficient. In the example below the recursive call by _range to
       itself is in tail position. The example shows  off  three  advanced  topics:  tail  recursion,  generator
       construction, and sub-functions.

           jq ´def range(init; upto; by): def _range: if (by > 0 and . < upto) or (by < 0 and . > upto) then ., ((.+by)|_range) else . end; if by == 0 then init else init|_range end | select((by > 0 and . < upto) or (by < 0 and . > upto)); range(0; 10; 3)´
              null
           => 0, 3, 6, 9

           jq ´def while(cond; update): def _while: if cond then ., (update | _while) else empty end; _while; [while(.<100; .*2)]´
              1
           => [1,2,4,8,16,32,64]

MATH

       jq currently only has IEEE754 double-precision (64-bit) floating point number support.

       Besides  simple  arithmetic operators such as +, jq also has most standard math functions from the C math
       library. C math functions that take a single input argument (e.g., sin()) are available as  zero-argument
       jq  functions. C math functions that take two input arguments (e.g., pow()) are available as two-argument
       jq functions that ignore ..

       Availability of standard math functions depends on the availability of the corresponding  math  functions
       in your operating system and C math library. Unavailable math functions will be defined but will raise an
       error.

I/O

       At this time jq has minimal support for I/O, mostly in the form of control over when inputs are read. Two
       builtins functions are provided for this, input and inputs, that read from the same sources (e.g., stdin,
       files named on the command-line) as jq itself. These two builtins, and jq´s own reading actions,  can  be
       interleaved with each other.

       One  builtin  provides  minimal output capabilities, debug. (Recall that a jq program´s output values are
       always output as JSON texts on stdout.) The debug builtin can have application-specific behavior, such as
       for executables that use the libjq C API but aren´t the jq executable itself.

   input
       Outputs one new input.

   inputs
       Outputs all remaining inputs, one by one.

       This is primarily useful for reductions over a program´s inputs.

   debug
       Causes  a  debug message based on the input value to be produced. The jq executable wraps the input value
       with ["DEBUG:", <input-value>] and prints that and a newline on stderr, compactly. This may change in the
       future.

   input_filename
       Returns  the  name of the file whose input is currently being filtered. Note that this will not work well
       unless jq is running in a UTF-8 locale.

   input_line_number
       Returns the line number of the input currently being filtered.

STREAMING

       With the --stream option jq can parse input texts in a streaming fashion, allowing jq programs  to  start
       processing  large JSON texts immediately rather than after the parse completes. If you have a single JSON
       text that is 1GB in size, streaming it will allow you to process it much more quickly.

       However, streaming isn´t easy to deal with as the jq program will have [<path>, <leaf-value>] (and a  few
       other forms) as inputs.

       Several builtins are provided to make handling streams easier.

       The examples below use the the streamed form of [0,[1]], which is [[0],0],[[1,0],1],[[1,0]],[[1]].

       Streaming  forms  include  [<path>,  <leaf-value>]  (to  indicate any scalar value, empty array, or empty
       object), and [<path>] (to indicate the end of an array  or  object).  Future  versions  of  jq  run  with
       --stream  and  -seq  may  output  additional  forms such as ["error message"] when an input text fails to
       parse.

   truncate_stream(stream_expression)
       Consumes a number as input and truncates the corresponding number of path elements from the left  of  the
       outputs of the given streaming expression.

           jq ´[1|truncate_stream([[0],1],[[1,0],2],[[1,0]],[[1]])]´
              1
           => [[[0],2],[[0]]]

   fromstream(stream_expression)
       Outputs values corresponding to the stream expression´s outputs.

           jq ´fromstream(1|truncate_stream([[0],1],[[1,0],2],[[1,0]],[[1]]))´
              null
           => [2]

   tostream
       The tostream builtin outputs the streamed form of its input.

           jq ´. as $dot|fromstream($dot|tostream)|.==$dot´
              [0,[1,{"a":1},{"b":2}]]
           => true

ASSIGNMENT

       Assignment  works  a  little differently in jq than in most programming languages. jq doesn´t distinguish
       between references to and copies of something - two objects or arrays are  either  equal  or  not  equal,
       without any further notion of being "the same object" or "not the same object".

       If  an object has two fields which are arrays, .foo and .bar, and you append something to .foo, then .bar
       will not get bigger. Even if you´ve just set .bar = .foo. If you´re used to programming in languages like
       Python, Java, Ruby, Javascript, etc. then you can think of it as though jq does a full deep copy of every
       object before it does the assignment (for performance, it  doesn´t  actually  do  that,  but  that´s  the
       general idea).

       All the assignment operators in jq have path expressions on the left-hand side.

   =
       The filter .foo = 1 will take as input an object and produce as output an object with the "foo" field set
       to 1. There is no notion of "modifying" or "changing" something in jq - all jq values are immutable.  For
       instance,

       .foo = .bar | .foo.baz = 1

       will  not  have  the  side-effect  of  setting .bar.baz to be set to 1, as the similar-looking program in
       Javascript, Python, Ruby or other languages would. Unlike these languages  (but  like  Haskell  and  some
       other  functional  languages), there is no notion of two arrays or objects being "the same array" or "the
       same object". They can be equal, or not equal, but if we change one of them in no circumstances will  the
       other change behind our backs.

       This  means  that it´s impossible to build circular values in jq (such as an array whose first element is
       itself). This is quite intentional, and ensures that anything a jq program can produce can be represented
       in JSON.

       Note  that  the  left-hand  side  of ´=´ refers to a value in .. Thus $var.foo = 1 won´t work as expected
       ($var.foo is not a valid or useful path expression in .); use $var | .foo = 1 instead.

       If the right-hand side of ´=´ produces multiple values, then for each such value jq will set the paths on
       the  left-hand  side  to  the value and then it will output the modified .. For example, (.a,.b)=range(2)
       outputs {"a":0,"b":0}, then {"a":1,"b":1}. The "update" assignment forms (see below) do not do this.

       Note too that .a,.b=0 does not set .a and .b, but (.a,.b)=0 sets both.

   |=
       As well as the assignment operator ´=´, jq provides the "update" operator ´|=´, which takes a  filter  on
       the  right-hand  side  and works out the new value for the property of . being assigned to by running the
       old value through this expression. For instance, .foo |= .+1 will build an object with  the  "foo"  field
       set to the input´s "foo" plus 1.

       This example should show the difference between ´=´ and ´|=´:

       Provide input ´{"a": {"b": 10}, "b": 20}´ to the programs:

       .a = .b .a |= .b

       The  former  will  set  the  "a" field of the input to the "b" field of the input, and produce the output
       {"a": 20}. The latter will set the "a" field of the input to the "a" field´s "b" field,  producing  {"a":
       10}.

       The left-hand side can be any general path expression; see path().

       Note  that  the  left-hand  side  of  ´|=´  refers  to a value in .. Thus $var.foo |= . + 1 won´t work as
       expected ($var.foo is not a valid or useful path expression in .); use $var | .foo |= . + 1 instead.

       If the right-hand side outputs multiple values, only the last one will be used.

           jq ´(..|select(type=="boolean")) |= if . then 1 else 0 end´
              [true,false,[5,true,[true,[false]],false]]
           => [1,0,[5,1,[1,[0]],0]]

   +=, -=, *=, /=, %=, //=
       jq has a few operators of the form a op= b, which are all equivalent to a |= . op b. So, += 1 can be used
       to increment values.

           jq ´.foo += 1´
              {"foo": 42}
           => {"foo": 43}

   Complex assignments
       Lots  more  things  are  allowed  on  the left-hand side of a jq assignment than in most languages. We´ve
       already seen simple field accesses on the left hand side, and it´s no surprise that array  accesses  work
       just as well:

           .posts[0].title = "JQ Manual"

       What may come as a surprise is that the expression on the left may produce multiple results, referring to
       different points in the input document:

           .posts[].comments |= . + ["this is great"]

       That example appends the string "this is great" to the "comments" array of each post in the input  (where
       the input is an object with a field "posts" which is an array of posts).

       When  jq encounters an assignment like ´a = b´, it records the "path" taken to select a part of the input
       document while executing a. This path is then used to find which  part  of  the  input  to  change  while
       executing  the assignment. Any filter may be used on the left-hand side of an equals - whichever paths it
       selects from the input will be where the assignment is performed.

       This is a very powerful operation. Suppose we wanted to add a comment  to  blog  posts,  using  the  same
       "blog"  input  above.  This time, we only want to comment on the posts written by "stedolan". We can find
       those posts using the "select" function described earlier:

           .posts[] | select(.author == "stedolan")

       The paths provided by this operation point to each of the posts that "stedolan" wrote, and we can comment
       on each of them in the same way that we did before:

           (.posts[] | select(.author == "stedolan") | .comments) |=
               . + ["terrible."]

MODULES

       jq has a library/module system. Modules are files whose names end in .jq.

       Modules  imported  by  a  program  are  searched for in a default search path (see below). The import and
       include directives allow the importer to alter this path.

       Paths in the a search path are subject to various substitutions.

       For paths starting with "~/", the user´s home directory is substituted for "~".

       For paths starting with "$ORIGIN/", the path of the jq executable is substituted for "$ORIGIN".

       For paths starting with "./" or paths that are ".", the path of the including  file  is  substituted  for
       ".". For top-level programs given on the command-line, the current directory is used.

       Import directives can optionally specify a search path to which the default is appended.

       The  default  search  path  is  the  search  path  given  to  the  -L command-line option, else ["~/.jq",
       "$ORIGIN/../lib/jq", "$ORIGIN/../lib"].

       Null and empty string path elements terminate search path processing.

       A dependency with relative path "foo/bar" would be searched for in "foo/bar.jq" and  "foo/bar/bar.jq"  in
       the  given  search  path.  This  is intended to allow modules to be placed in a directory along with, for
       example, version control files, README files, and so on, but also to allow for single-file modules.

       Consecutive components with the same name are not allowed to avoid ambiguities (e.g., "foo/foo").

       For example, with -L$HOME/.jq a module foo can be found in $HOME/.jq/foo.jq and $HOME/.jq/foo/foo.jq.

       If "$HOME/.jq" is a file, it is sourced into the main program.

   import RelativePathString as NAME [<metadata>];
       Imports a module found at the given path relative to a directory in a search path. A ".jq" suffix will be
       added to the relative path string. The module´s symbols are prefixed with "NAME::".

       The  optional metadata must be a constant jq expression. It should be an object with keys like "homepage"
       and so on. At this time jq only uses the "search" key/value of the metadata. The metadata  is  also  made
       available to users via the modulemeta builtin.

       The  "search"  key  in  the metadata, if present, should have a string or array value (array of strings);
       this is the search path to be prefixed to the top-level search path.

   include RelativePathString [<metadata>];
       Imports a module found at the given path relative to a directory in a search path as if it were  included
       in  place.  A  ".jq"  suffix will be added to the relative path string. The module´s symbols are imported
       into the caller´s namespace as if the module´s content had been included directly.

       The optional metadata must be a constant jq expression. It should be an object with keys like  "homepage"
       and  so  on.  At this time jq only uses the "search" key/value of the metadata. The metadata is also made
       available to users via the modulemeta builtin.

   import RelativePathString as $NAME [<metadata>];
       Imports a JSON file found at the given path relative to a directory in a search path.  A  ".json"  suffix
       will be added to the relative path string. The file´s data will be available as $NAME::NAME.

       The  optional metadata must be a constant jq expression. It should be an object with keys like "homepage"
       and so on. At this time jq only uses the "search" key/value of the metadata. The metadata  is  also  made
       available to users via the modulemeta builtin.

       The  "search"  key  in  the metadata, if present, should have a string or array value (array of strings);
       this is the search path to be prefixed to the top-level search path.

   module <metadata>;
       This directive is entirely optional. It´s not required for proper operation. It serves only  the  purpose
       of providing metadata that can be read with the modulemeta builtin.

       The  metadata must be a constant jq expression. It should be an object with keys like "homepage". At this
       time jq doesn´t use this metadata, but it is made available to users via the modulemeta builtin.

   modulemeta
       Takes a module name as input and outputs the module´s metadata as an object, with  the  module´s  imports
       (including metadata) as an array value for the "deps" key.

       Programs  can  use  this  to query a module´s metadata, which they could then use to, for example, search
       for, download, and install missing dependencies.

BUGS

       Presumably. Report them or discuss them at:

           https://github.com/stedolan/jq/issues

AUTHOR

       Stephen Dolan <mu@netsoc.tcd.ie>

                                                  January 2017                                             JQ(1)