NAME

       StdLabels.List - no description

Module

       Module   StdLabels.List

Documentation

       Module List
        : (module ListLabels)

       val length : 'a list -> int

       Return the length (number of elements) of the given list.

       val hd : 'a list -> 'a

       Return the first element of the given list. Raise Failure hd if the list is empty.

       val tl : 'a list -> 'a list

       Return the given list without its first element. Raise Failure tl if the list is empty.

       val nth : 'a list -> int -> 'a

       Return  the  n  -th element of the given list.  The first element (head of the list) is at
       position 0.  Raise Failure nth if the list is too short.  Raise Invalid_argument  List.nth
       if n is negative.

       val rev : 'a list -> 'a list

       List reversal.

       val append : 'a list -> 'a list -> 'a list

       Catenate  two  lists.  Same function as the infix operator @ .  Not tail-recursive (length
       of the first argument).  The @ operator is not tail-recursive either.

       val rev_append : 'a list -> 'a list -> 'a list

       ListLabels.rev_append l1 l2 reverses l1 and concatenates it to l2 .  This is equivalent to
       ListLabels.rev l1 @ l2 , but rev_append is tail-recursive and more efficient.

       val concat : 'a list list -> 'a list

       Concatenate  a  list of lists.  The elements of the argument are all concatenated together
       (in the same order) to give the result.  Not tail-recursive  (length  of  the  argument  +
       length of the longest sub-list).

       val flatten : 'a list list -> 'a list

       Same  as  concat  .   Not  tail-recursive  (length of the argument + length of the longest
       sub-list).

       === Iterators ===

       val iter : f:('a -> unit) -> 'a list -> unit

       ListLabels.iter f [a1; ...; an] applies function f  in  turn  to  a1;  ...;  an  .  It  is
       equivalent to begin f a1; f a2; ...; f an; () end .

       val iteri : f:(int -> 'a -> unit) -> 'a list -> unit

       Same as ListLabels.iter , but the function is applied to the index of the element as first
       argument (counting from 0), and the element itself as second argument.

       Since 4.00.0

       val map : f:('a -> 'b) -> 'a list -> 'b list

       ListLabels.map f [a1; ...; an] applies function f to a1, ..., an , and builds the list  [f
       a1; ...; f an] with the results returned by f .  Not tail-recursive.

       val mapi : f:(int -> 'a -> 'b) -> 'a list -> 'b list

       Same  as ListLabels.map , but the function is applied to the index of the element as first
       argument (counting from 0), and the element itself as second argument.

       Since 4.00.0

       val rev_map : f:('a -> 'b) -> 'a list -> 'b list

       ListLabels.rev_map f l gives the same result as ListLabels.rev ( ListLabels.map f l) , but
       is tail-recursive and more efficient.

       val fold_left : f:('a -> 'b -> 'a) -> init:'a -> 'b list -> 'a

       ListLabels.fold_left f a [b1; ...; bn] is f (... (f (f a b1) b2) ...) bn .

       val fold_right : f:('a -> 'b -> 'b) -> 'a list -> init:'b -> 'b

       ListLabels.fold_right  f  [a1;  ...;  an]  b  is  f  a1  (f a2 (... (f an b) ...))  .  Not
       tail-recursive.

       === Iterators on two lists ===

       val iter2 : f:('a -> 'b -> unit) -> 'a list -> 'b list -> unit

       ListLabels.iter2 f [a1; ...; an] [b1; ...; bn] calls in turn f a1  b1;  ...;  f  an  bn  .
       Raise Invalid_argument if the two lists have different lengths.

       val map2 : f:('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list

       ListLabels.map2  f  [a1;  ...;  an]  [b1;  ...;  bn]  is  [f a1 b1; ...; f an bn] .  Raise
       Invalid_argument if the two lists have different lengths.  Not tail-recursive.

       val rev_map2 : f:('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list

       ListLabels.rev_map2 f l1 l2 gives the same result as ListLabels.rev ( ListLabels.map2 f l1
       l2) , but is tail-recursive and more efficient.

       val fold_left2 : f:('a -> 'b -> 'c -> 'a) -> init:'a -> 'b list -> 'c list -> 'a

       ListLabels.fold_left2 f a [b1; ...; bn] [c1; ...; cn] is f (... (f (f a b1 c1) b2 c2) ...)
       bn cn .  Raise Invalid_argument if the two lists have different lengths.

       val fold_right2 : f:('a -> 'b -> 'c -> 'c) -> 'a list -> 'b list -> init:'c -> 'c

       ListLabels.fold_right2 f [a1; ...; an] [b1; ...; bn] c is f a1 b1 (f a2 b2 (... (f  an  bn
       c)  ...))   .   Raise  Invalid_argument  if  the  two  lists  have different lengths.  Not
       tail-recursive.

       === List scanning ===

       val for_all : f:('a -> bool) -> 'a list -> bool

       for_all p [a1; ...; an] checks if all elements of the list satisfy the predicate p .  That
       is, it returns (p a1) && (p a2) && ... && (p an) .

       val exists : f:('a -> bool) -> 'a list -> bool

       exists  p [a1; ...; an] checks if at least one element of the list satisfies the predicate
       p . That is, it returns (p a1) || (p a2) || ... || (p an) .

       val for_all2 : f:('a -> 'b -> bool) -> 'a list -> 'b list -> bool

       Same as ListLabels.for_all , but for a two-argument predicate.  Raise Invalid_argument  if
       the two lists have different lengths.

       val exists2 : f:('a -> 'b -> bool) -> 'a list -> 'b list -> bool

       Same  as  ListLabels.exists , but for a two-argument predicate.  Raise Invalid_argument if
       the two lists have different lengths.

       val mem : 'a -> set:'a list -> bool

       mem a l is true if and only if a is equal to an element of l .

       val memq : 'a -> set:'a list -> bool

       Same as ListLabels.mem , but uses physical equality  instead  of  structural  equality  to
       compare list elements.

       === List searching ===

       val find : f:('a -> bool) -> 'a list -> 'a

       find  p  l returns the first element of the list l that satisfies the predicate p .  Raise
       Not_found if there is no value that satisfies p in the list l .

       val filter : f:('a -> bool) -> 'a list -> 'a list

       filter p l returns all the elements of the list l that satisfy  the  predicate  p  .   The
       order of the elements in the input list is preserved.

       val find_all : f:('a -> bool) -> 'a list -> 'a list

       find_all is another name for ListLabels.filter .

       val partition : f:('a -> bool) -> 'a list -> 'a list * 'a list

       partition  p l returns a pair of lists (l1, l2) , where l1 is the list of all the elements
       of l that satisfy the predicate p , and l2 is the list of all the elements of  l  that  do
       not satisfy p .  The order of the elements in the input list is preserved.

       === Association lists ===

       val assoc : 'a -> ('a * 'b) list -> 'b

       assoc  a l returns the value associated with key a in the list of pairs l . That is, assoc
       a [ ...; (a,b); ...] = b if (a,b) is the  leftmost  binding  of  a  in  list  l  .   Raise
       Not_found if there is no value associated with a in the list l .

       val assq : 'a -> ('a * 'b) list -> 'b

       Same  as  ListLabels.assoc  , but uses physical equality instead of structural equality to
       compare keys.

       val mem_assoc : 'a -> map:('a * 'b) list -> bool

       Same as ListLabels.assoc , but simply return true if a binding exists,  and  false  if  no
       bindings exist for the given key.

       val mem_assq : 'a -> map:('a * 'b) list -> bool

       Same  as  ListLabels.mem_assoc , but uses physical equality instead of structural equality
       to compare keys.

       val remove_assoc : 'a -> ('a * 'b) list -> ('a * 'b) list

       remove_assoc a l returns the list of pairs l without the first pair with key a ,  if  any.
       Not tail-recursive.

       val remove_assq : 'a -> ('a * 'b) list -> ('a * 'b) list

       Same  as  ListLabels.remove_assoc  ,  but  uses  physical  equality  instead of structural
       equality to compare keys.  Not tail-recursive.

       === Lists of pairs ===

       val split : ('a * 'b) list -> 'a list * 'b list

       Transform a list of pairs into a pair of lists: split [(a1,b1);  ...;  (an,bn)]  is  ([a1;
       ...; an], [b1; ...; bn]) .  Not tail-recursive.

       val combine : 'a list -> 'b list -> ('a * 'b) list

       Transform  a  pair  of  lists into a list of pairs: combine [a1; ...; an] [b1; ...; bn] is
       [(a1,b1); ...; (an,bn)] .  Raise Invalid_argument if the two lists have different lengths.
       Not tail-recursive.

       === Sorting ===

       val sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list

       Sort  a  list  in  increasing  order  according  to a comparison function.  The comparison
       function must return 0 if its arguments compare as equal, a positive integer if the  first
       is  greater, and a negative integer if the first is smaller (see Array.sort for a complete
       specification).  For example, Pervasives.compare is a suitable comparison  function.   The
       resulting  list  is  sorted  in increasing order.  ListLabels.sort is guaranteed to run in
       constant heap space (in addition to the size of the result  list)  and  logarithmic  stack
       space.

       The current implementation uses Merge Sort. It runs in constant heap space and logarithmic
       stack space.

       val stable_sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list

       Same as ListLabels.sort , but the sorting algorithm  is  guaranteed  to  be  stable  (i.e.
       elements that compare equal are kept in their original order) .

       The current implementation uses Merge Sort. It runs in constant heap space and logarithmic
       stack space.

       val fast_sort : cmp:('a -> 'a -> int) -> 'a list -> 'a list

       Same as ListLabels.sort or ListLabels.stable_sort , whichever is faster on typical input.

       val merge : cmp:('a -> 'a -> int) -> 'a list -> 'a list -> 'a list

       Merge two lists: Assuming that l1 and l2 are sorted according to the  comparison  function
       cmp  , merge cmp l1 l2 will return a sorted list containting all the elements of l1 and l2
       .  If several elements compare equal, the elements of l1 will be before the elements of l2
       .  Not tail-recursive (sum of the lengths of the arguments).