Ubuntu Manpage: doctools::idx - Holding keyword indices

NAME

       doctools::idx - Holding keyword indices

SYNOPSIS

       package require doctools::idx  ?2?

       package require Tcl  8.4

       package require doctools::idx::structure

       package require snit

       ::doctools::idx objectName

       objectName method ?arg arg ...?

       objectName destroy

       objectName key add name

       objectName key remove name

       objectName key references name

       objectName keys

       objectName reference add type key name label

       objectName reference remove name

       objectName reference label name

       objectName reference keys name

       objectName reference type name

       objectName references

       objectName title

       objectName title text

       objectName label

       objectName label text

       objectName importer

       objectName importer object

       objectName exporter

       objectName exporter object

       objectName deserialize = data ?format?

       objectName deserialize += data ?format?

       objectName serialize ?format?

_________________________________________________________________________________________________

DESCRIPTION

       This package provides a class to contain and programmatically manipulate keyword indices

       This  is one of the three public pillars the management of keyword indices resides on. The
       other two pillars are

       [1]    Exporting keyword indices, and

       [2]    Importing keyword indices

       For information about the Concepts of keyword indices, and their parts, see the same-named
       section.  For information about the data structure which is used to encode keyword indices
       as values see the section Keyword index serialization format.  This  is  the  only  format
       directly  known  to  this  class.  Conversions from and to any other format are handled by
       export and import manager objects. These may be attached to a container, but do  not  have
       to be, it is merely a convenience.

CONCEPTS

       [1]    A keyword index consists of a (possibly empty) set of keywords.

       [2]    Each keyword in the set is identified by its name.

       [3]    Each keyword has a (possibly empty) set of references.

       [4]    A reference can be associated with more than one keyword.

       [5]    A reference not associated with at least one keyword is not possible however.

       [6]    Each  reference is identified by its target, specified as either an url or symbolic
              filename, depending on the type of reference (url, or manpage).

       [7]    The type of a reference (url, or manpage) depends only on the reference itself, and
              not the keywords it is associated with.

       [8]    In  addition  to  a type each reference has a descriptive label as well. This label
              depends only on the reference itself, and not the keywords it is associated with.

       A few notes

       [1]    Manpage references are intended to be used for  references  to  the  documents  the
              index  is  made for. Their target is a symbolic file name identifying the document,
              and export plugins may replace symbolic with actual file names, if specified.

       [2]    Url references are intended on the othre hand are inteded to be used for  links  to
              anything else, like websites. Their target is an url.

       [3]    While  url  and  manpage  references  share a namespace for their identifiers, this
              should be no problem, given that manpage identifiers are symbolic filenames and  as
              such they should never look like urls, the identifiers for url references.

API

PACKAGE COMMANDS
::doctools::idx objectName
This command creates a new container object with an associated Tcl command whose
name is objectName. This object command is explained in full detail in the sections
Object command and Object methods. The object command will be created under the
current namespace if the objectName is not fully qualified, and in the specified
namespace otherwise.

OBJECT COMMAND
All objects created by the ::doctools::idx command have the following general form:

objectName method ?arg arg ...?
The method method and its arg'uments determine the exact behavior of the command.
See section Object methods for the detailed specifications.

OBJECT METHODS
objectName destroy
This method destroys the object it is invoked for.

objectName key add name
This method adds the keyword name to the index. If the keyword is already known
nothing is done. The result of the method is the empty string.

objectName key remove name
This method removes the keyword name from the index. If the keyword is already gone
nothing is done. Any references for whom this keyword was the last association are
removed as well. The result of the method is the empty string.

objectName key references name
This method returns a list containing the names of all references associated with
the keyword name. An error is thrown in the keyword is not known to the index. The
order of the references in the list is undefined.

objectName keys
This method returns a list containing the names of all keywords known to the index.
The order of the keywords in the list is undefined.

objectName reference add type key name label
This method adds the reference name to the index and associates it with the keyword
key. The other two arguments hold the type and label of the reference,
respectively. The type has to match the stored information, should the reference
exist already, i.e. this information is immutable after the reference is known. The
only way to change it is delete and recreate the reference. The label on the other
hand is automatically updated to the value of the argument, overwriting any
previously stored information. Should the reference exists already it is simply
associated with the key. If that is true already as well nothing is done, but the
label updated to the new value. The result of the method is the empty string.

The type argument has be to one of manpage or url.

objectName reference remove name
The reference name is removed from the index. All associations with keywords are
released and the relevant reference labels removed. The result of the method is
the empty string.

objectName reference label name
This method returns the label associated with the reference name. An error is
thrown if the reference is not known.

objectName reference keys name
This method returns a list containing the names of all keywords associated with the
reference name. An error is thrown in the reference is not known to the index. The
order of the keywords in the list is undefined.

objectName reference type name
This method returns the type of the reference name. An error is thrown in the
reference is not known to the index.

objectName references
This method returns a list containing the names of all references known to the
index. The order of the references in the list is undefined.

objectName title
Returns the currently defined title of the keyword index.

objectName title text
Sets the title of the keyword index to text, and returns it as the result of the
command.

objectName label
Returns the currently defined label of the keyword index.

objectName label text
Sets the label of the keyword index to text, and returns it as the result of the
command.

objectName importer
Returns the import manager object currently attached to the container, if any.

objectName importer object
Attaches the object as import manager to the container, and returns it as the
result of the command. Note that the object is not put into ownership of the
container. I.e., destruction of the container will not destroy the object.

It is expected that object provides a method named import text which takes a text
and a format name, and returns the canonical serialization of the keyword index
contained in the text, assuming the given format.

objectName exporter
Returns the export manager object currently attached to the container, if any.

objectName exporter object
Attaches the object as export manager to the container, and returns it as the
result of the command. Note that the object is not put into ownership of the
container. I.e., destruction of the container will not destroy the object.

It is expected that object provides a method named export object which takes the
container and a format name, and returns a text encoding keyword index stored in
the container, in the given format. It is further expected that the object will use
the container's method serialize to obtain the serialization of the keyword index
from which to generate the text.

objectName deserialize = data ?format?
This method replaces the contents of the index object with the index contained in
the data. If no format was specified it is assumed to be the regular serialization
of a keyword index.

Otherwise the object will use the attached import manager to convert the data from
the specified format to a serialization it can handle. In that case an error will
be thrown if the container has no import manager attached to it.

The result of the method is the empty string.

objectName deserialize += data ?format?
This method behaves like deserialize = in its essentials, except that it merges the
keyword index in the data to its contents instead of replacing it. The method will
throw an error if merging is not possible, i.e. would produce an invalid index. The
existing content is left unchanged in that case.

The result of the method is the empty string.

objectName serialize ?format?
This method returns the keyword index contained in the object. If no format is not
specified the returned result is the canonical serialization of its contents.

Otherwise the object will use the attached export manager to convert the data to
the specified format. In that case an error will be thrown if the container has no
export manager attached to it.

KEYWORD INDEX SERIALIZATION FORMAT

Here we specify the format used by the doctools v2 packages to serialize keyword indices
as immutable values for transport, comparison, etc.

We distinguish between regular and canonical serializations. While a keyword index may
have more than one regular serialization only exactly one of them will be canonical.

regular serialization

[1] An index serialization is a nested Tcl dictionary.

[2] This dictionary holds a single key, doctools::idx, and its value. This value
holds the contents of the index.

[3] The contents of the index are a Tcl dictionary holding the title of the
index, a label, and the keywords and references. The relevant keys and their
values are

title The value is a string containing the title of the index.

label The value is a string containing a label for the index.

keywords
The value is a Tcl dictionary, using the keywords known to the index
as keys. The associated values are lists containing the identifiers
of the references associated with that particular keyword.

Any reference identifier used in these lists has to exist as a key in
the references dictionary, see the next item for its definition.

references
The value is a Tcl dictionary, using the identifiers for the
references known to the index as keys. The associated values are
2-element lists containing the type and label of the reference, in
this order.

Any key here has to be associated with at least one keyword, i.e.
occur in at least one of the reference lists which are the values in
the keywords dictionary, see previous item for its definition.

[4] The type of a reference can be one of two values,

manpage
The identifier of the reference is interpreted as symbolic file name,
referring to one of the documents the index was made for.

url The identifier of the reference is interpreted as an url, referring
to some external location, like a website, etc.

canonical serialization
The canonical serialization of a keyword index has the format as specified in the
previous item, and then additionally satisfies the constraints below, which make it
unique among all the possible serializations of the keyword index.

[1] The keys found in all the nested Tcl dictionaries are sorted in ascending
dictionary order, as generated by Tcl's builtin command lsort -increasing
-dict.

[2] The references listed for each keyword of the index, if any, are listed in
ascending dictionary order of their labels, as generated by Tcl's builtin
command lsort -increasing -dict.

BUGS, IDEAS, FEEDBACK

       This document, and the package it describes,  will  undoubtedly  contain  bugs  and  other
       problems.    Please   report  such  in  the  category  doctools  of  the  Tcllib  Trackers
       [http://core.tcl.tk/tcllib/reportlist].  Please also report any ideas for enhancements you
       may have for either package and/or documentation.

       When proposing code changes, please provide unified diffs, i.e the output of diff -u.

       Note further that attachments are strongly preferred over inlined patches. Attachments can
       be made by going to the Edit form of the ticket immediately after its creation,  and  then
       using the left-most button in the secondary navigation bar.

KEYWORDS

       HTML, TMML, conversion, docidx markup, documentation, formatting, generation, index, json,
       keyword index, latex, manpage, markup, nroff, parsing, plugin,  reference,  tcler's  wiki,
       text, url, wiki

COPYRIGHT

       Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>