Provided by: tcllib_1.17-dfsg-1_all 
NAME
doctools::idx::structure - Docidx serialization utilities
SYNOPSIS
package require doctools::idx::structure ?0.1?
package require Tcl 8.4
package require logger
package require snit
::doctools::idx::structure verify serial ?canonvar?
::doctools::idx::structure verify-as-canonical serial
::doctools::idx::structure canonicalize serial
::doctools::idx::structure print serial
::doctools::idx::structure merge seriala serialb
_________________________________________________________________________________________________
DESCRIPTION
This package provides commands to work with the serializations of keyword indices as
managed by the doctools system v2, and specified in section Keyword index serialization
format.
This is an internal package of doctools, for use by the higher level packages handling
keyword indices and their conversion into and out of various other formats, like documents
written using docidx markup.
API
::doctools::idx::structure verify serial ?canonvar?
This command verifies that the content of serial is a valid regular serialization
of a keyword index and will throw an error if that is not the case. The result of
the command is the empty string.
If the argument canonvar is specified it is interpreted as the name of a variable
in the calling context. This variable will be written to if and only if serial is a
valid regular serialization. Its value will be a boolean, with True indicating that
the serialization is not only valid, but also canonical. False will be written for
a valid, but non-canonical serialization.
For the specification of regular and canonical keyword index serializations see the
section Keyword index serialization format.
::doctools::idx::structure verify-as-canonical serial
This command verifies that the content of serial is a valid canonical serialization
of a keyword index and will throw an error if that is not the case. The result of
the command is the empty string.
For the specification of canonical keyword index serializations see the section
Keyword index serialization format.
::doctools::idx::structure canonicalize serial
This command assumes that the content of serial is a valid regular serialization of
a keyword index and will throw an error if that is not the case.
It will then convert the input into the canonical serialization of the contained
keyword index and return it as its result. If the input is already canonical it
will be returned unchanged.
For the specification of regular and canonical keyword index serializations see the
section Keyword index serialization format.
::doctools::idx::structure print serial
This command assumes that the argument serial contains a valid regular
serialization of a keyword index and returns a string containing that index in a
human readable form.
The exact format of this form is not specified and cannot be relied on for parsing
or other machine-based activities.
For the specification of regular keyword index serializations see the section
Keyword index serialization format.
::doctools::idx::structure merge seriala serialb
This command accepts the regular serializations of two keyword indices and uses
them to create their union. The result of the command is the canonical
serialization of this unified keyword index.
Title and label of the resulting index are taken from the index contained in
serialb. The set of keys, references and their connections is the union of the set
of keys and references of the two inputs.
For the specification of regular and canonical keyword index serializations see the
section Keyword index serialization format.
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,
refering to one of the documents the index was made for.
url The identifier of the reference is interpreted as an url, refering 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.
KEYWORDS
deserialization, docidx, doctools, serialization
CATEGORY
Documentation tools
COPYRIGHT
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>