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'\"
'\" Generated from file 'toc_import\&.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>
'\"
.TH "doctools::toc::import" n 0\&.1 tcllib "Documentation tools"
.\" The -*- nroff -*- definitions below are for supplemental macros used
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.BS
.SH NAME
doctools::toc::import \- Importing keyword indices
.SH SYNOPSIS
package require \fBdoctools::toc::import  ?0\&.1?\fR
.sp
package require \fBTcl  8\&.4\fR
.sp
package require \fBdoctools::config \fR
.sp
package require \fBdoctools::toc::structure \fR
.sp
package require \fBsnit \fR
.sp
package require \fBpluginmgr \fR
.sp
\fB::doctools::toc::import\fR \fIobjectName\fR
.sp
\fBobjectName\fR \fBmethod\fR ?\fIarg arg \&.\&.\&.\fR?
.sp
\fIobjectName\fR \fBdestroy\fR
.sp
\fIobjectName\fR \fBimport text\fR \fItext\fR ?\fIformat\fR?
.sp
\fIobjectName\fR \fBimport file\fR \fIpath\fR ?\fIformat\fR?
.sp
\fIobjectName\fR \fBimport object text\fR \fIobject\fR \fItext\fR ?\fIformat\fR?
.sp
\fIobjectName\fR \fBimport object file\fR \fIobject\fR \fIpath\fR ?\fIformat\fR?
.sp
\fIobjectName\fR \fBconfig names\fR
.sp
\fIobjectName\fR \fBconfig get\fR
.sp
\fIobjectName\fR \fBconfig set\fR \fIname\fR ?\fIvalue\fR?
.sp
\fIobjectName\fR \fBconfig unset\fR \fIpattern\fR\&.\&.\&.
.sp
\fIobjectName\fR \fBincludes\fR
.sp
\fIobjectName\fR \fBinclude add\fR \fIpath\fR
.sp
\fIobjectName\fR \fBinclude remove\fR \fIpath\fR
.sp
\fIobjectName\fR \fBinclude clear\fR
.sp
\fBIncludeFile\fR \fIcurrentfile\fR \fIpath\fR
.sp
\fBimport\fR \fItext\fR \fIconfiguration\fR
.sp
.BE
.SH DESCRIPTION
This package provides a class to manage the plugins for the import of
tables of contents from other formats, i\&.e\&. their conversion from, for
example \fIdoctoc\fR, \fIjson\fR, etc\&.
.PP
This is one of the three public pillars the management of tables of
contents resides on\&. The other two pillars are
.IP [1]
\fIExporting tables of contents\fR, and
.IP [2]
\fIHolding tables of contents\fR
.PP
.PP
For information about the \fBConcepts\fR of tables of contents,
and their parts, see the same-named section\&.
For information about the data structure which is the major output of
the manager objects provided by this package see the section
\fBToC serialization format\fR\&.
.PP
The plugin system of our class is based on the package
\fBpluginmgr\fR, and configured to look for plugins using
.IP [1]
the environment variable \fBDOCTOOLS_TOC_IMPORT_PLUGINS\fR,
.IP [2]
the environment variable \fBDOCTOOLS_TOC_PLUGINS\fR,
.IP [3]
the environment variable \fBDOCTOOLS_PLUGINS\fR,
.IP [4]
the path "\fI~/\&.doctools/toc/import/plugin\fR"
.IP [5]
the path "\fI~/\&.doctools/toc/plugin\fR"
.IP [6]
the path "\fI~/\&.doctools/plugin\fR"
.IP [7]
the path "\fI~/\&.doctools/toc/import/plugins\fR"
.IP [8]
the path "\fI~/\&.doctools/toc/plugins\fR"
.IP [9]
the path "\fI~/\&.doctools/plugins\fR"
.IP [10]
the registry entry "HKEY_CURRENT_USER\\SOFTWARE\\DOCTOOLS\\TOC\\IMPORT\\PLUGINS"
.IP [11]
the registry entry "HKEY_CURRENT_USER\\SOFTWARE\\DOCTOOLS\\TOC\\PLUGINS"
.IP [12]
the registry entry "HKEY_CURRENT_USER\\SOFTWARE\\DOCTOOLS\\PLUGINS"
.PP
The last three are used only when the package is run on a machine
using Windows(tm) operating system\&.
.PP
The whole system is delivered with two predefined import plugins,
namely
.TP
doctoc
See \fIdoctoc import plugin\fR for details\&.
.TP
json
See \fIjson import plugin\fR for details\&.
.PP
.PP
Readers wishing to write their own import plugin for some format, i\&.e\&.
\fIplugin writer\fRs reading and understanding the section
containing the \fBImport plugin API v2 reference\fR is an
absolute necessity, as it specifies the interaction between this
package and its plugins in detail\&.
.SH CONCEPTS
.IP [1]
A \fItable of contents\fR consists of a (possibly empty) list of
\fIelements\fR\&.
.IP [2]
Each element in the list is identified by its label\&.
.IP [3]
Each element is either a \fIreference\fR, or a \fIdivision\fR\&.
.IP [4]
Each reference has an associated document, identified by a symbolic
id, and a textual description\&.
.IP [5]
Each division may have an associated document, identified by a
symbolic id\&.
.IP [6]
Each division consists consists of a (possibly empty) list of
\fIelements\fR, with each element following the rules as specified in
item 2 and above\&.
.PP
A few notes
.IP [1]
The above rules span up a tree of elements, with references as the
leaf nodes, and divisions as the inner nodes, and each element
representing an entry in the whole table of contents\&.
.IP [2]
The identifying labels of any element E are unique within their
division (or toc), and the full label of any element E is the list of
labels for all nodes on the unique path from the root of the tree to
E, including E\&.
.PP
.SH API
.SS "PACKAGE COMMANDS"
.TP
\fB::doctools::toc::import\fR \fIobjectName\fR
This command creates a new import manager object with an associated
Tcl command whose name is \fIobjectName\fR\&. This \fIobject\fR command
is explained in full detail in the sections \fBObject command\fR
and \fBObject methods\fR\&. The object command will be created
under the current namespace if the \fIobjectName\fR is not fully
qualified, and in the specified namespace otherwise\&.
.PP
.SS "OBJECT COMMAND"
All objects created by the \fB::doctools::toc::import\fR command have
the following general form:
.TP
\fBobjectName\fR \fBmethod\fR ?\fIarg arg \&.\&.\&.\fR?
The method \fBmethod\fR and its \fIarg\fR'uments determine the
exact behavior of the command\&.
See section \fBObject methods\fR for the detailed
specifications\&.
.PP
.SS "OBJECT METHODS"
.TP
\fIobjectName\fR \fBdestroy\fR
This method destroys the object it is invoked for\&.
.TP
\fIobjectName\fR \fBimport text\fR \fItext\fR ?\fIformat\fR?
This method takes the \fItext\fR and converts it from the specified
\fIformat\fR to the canonical serialization of a table of contents using
the import plugin for the format\&. An error is thrown if no plugin
could be found for the format\&.
The serialization generated by the conversion process is returned as
the result of this method\&.
.sp
If no format is specified the method defaults to \fBdoctoc\fR\&.
.sp
The specification of what a \fIcanonical\fR serialization is can be
found in the section \fBToC serialization format\fR\&.
.sp
The plugin has to conform to the interface specified in section
\fBImport plugin API v2 reference\fR\&.
.TP
\fIobjectName\fR \fBimport file\fR \fIpath\fR ?\fIformat\fR?
This method is a convenient wrapper around the \fBimport text\fR
method described by the previous item\&.
It reads the contents of the specified file into memory, feeds the
result into \fBimport text\fR and returns the resulting
serialization as its own result\&.
.TP
\fIobjectName\fR \fBimport object text\fR \fIobject\fR \fItext\fR ?\fIformat\fR?
This method is a convenient wrapper around the \fBimport text\fR
method described by the previous item\&.
It expects that \fIobject\fR is an object command supporting a
\fBdeserialize\fR method expecting the canonical serialization of a
table of contents\&.
It imports the text using \fBimport text\fR and then feeds the
resulting serialization into the \fIobject\fR via \fBdeserialize\fR\&.
This method returns the empty string as it result\&.
.TP
\fIobjectName\fR \fBimport object file\fR \fIobject\fR \fIpath\fR ?\fIformat\fR?
This method behaves like \fBimport object text\fR, except that it
reads the text to convert from the specified file instead of being
given it as argument\&.
.TP
\fIobjectName\fR \fBconfig names\fR
This method returns a list containing the names of all configuration
variables currently known to the object\&.
.TP
\fIobjectName\fR \fBconfig get\fR
This method returns a dictionary containing the names and values of
all configuration variables currently known to the object\&.
.TP
\fIobjectName\fR \fBconfig set\fR \fIname\fR ?\fIvalue\fR?
This method sets the configuration variable \fIname\fR to the
specified \fIvalue\fR and returns the new value of the variable\&.
.sp
If no value is specified it simply returns the current value, without
changing it\&.
.sp
Note that while the user can set the predefined configuration
variables \fBuser\fR and \fBformat\fR doing so will have no
effect, these values will be internally overriden when invoking an
import plugin\&.
.TP
\fIobjectName\fR \fBconfig unset\fR \fIpattern\fR\&.\&.\&.
This method unsets all configuration variables matching the specified
glob \fIpattern\fRs\&. If no pattern is specified it will unset all
currently defined configuration variables\&.
.TP
\fIobjectName\fR \fBincludes\fR
This method returns a list containing the currently specified paths to
use to search for include files when processing input\&.
The order of paths in the list corresponds to the order in which they
are used, from first to last, and also corresponds to the order in
which they were added to the object\&.
.TP
\fIobjectName\fR \fBinclude add\fR \fIpath\fR
This methods adds the specified \fIpath\fR to the list of paths to use
to search for include files when processing input\&. The path is added
to the end of the list, causing it to be searched after all previously
added paths\&. The result of the command is the empty string\&.
.sp
The method does nothing if the path is already known\&.
.TP
\fIobjectName\fR \fBinclude remove\fR \fIpath\fR
This methods removes the specified \fIpath\fR from the list of paths
to use to search for include files when processing input\&. The result
of the command is the empty string\&.
.sp
The method does nothing if the path is not known\&.
.TP
\fIobjectName\fR \fBinclude clear\fR
This method clears the list of paths to use to search for include
files when processing input\&. The result of the command is the empty
string\&.
.PP
.SH "IMPORT PLUGIN API V2 REFERENCE"
Plugins are what this package uses to manage the support for any input
format beyond the \fBToC serialization format\fR\&. Here we
specify the API the objects created by this package use to interact
with their plugins\&.
.PP
A plugin for this package has to follow the rules listed below:
.IP [1]
A plugin is a package\&.
.IP [2]
The name of a plugin package has the form
doctools::toc::import::\fBFOO\fR,
where \fBFOO\fR is the name of the format the plugin will
generate output for\&. This name is also the argument to provide
to the various \fBimport\fR methods of import manager
objects to get a string encoding a table of contents in that
format\&.
.IP [3]
The plugin can expect that the package
\fBdoctools::toc::export::plugin\fR is present, as
indicator that it was invoked from a genuine plugin manager\&.
.IP [4]
The plugin can expect that a command named \fBIncludeFile\fR is
present, with the signature
.RS
.TP
\fBIncludeFile\fR \fIcurrentfile\fR \fIpath\fR
This command has to be invoked by the plugin when it has to process an
included file, if the format has the concept of such\&. An example of
such a format would be \fIdoctoc\fR\&.
.sp
The plugin has to supply the following arguments
.RS
.TP
string \fIcurrentfile\fR
The path of the file it is currently processing\&. This may be the empty
string if no such is known\&.
.TP
string \fIpath\fR
The path of the include file as specified in the include directive
being processed\&.
.RE
.IP
The result of the command will be a 5-element list containing
.RS
.IP [1]
A boolean flag indicating the success (\fBTrue\fR) or failure
(\fBFalse\fR) of the operation\&.
.IP [2]
In case of success the contents of the included file, and the
empty string otherwise\&.
.IP [3]
The resolved, i\&.e\&. absolute path of the included file, if
possible, or the unchanged \fIpath\fR argument\&. This is for
display in an error message, or as the \fIcurrentfile\fR
argument of another call to \fBIncludeFile\fR should this file
contain more files\&.
.IP [4]
In case of success an empty string, and for failure a code
indicating the reason for it, one of
.RS
.TP
notfound
The specified file could not be found\&.
.TP
notread
The specified file was found, but not be read into memory\&.
.RE
.IP [5]
An empty string in case of success of a \fBnotfound\fR
failure, and an additional error message describing the reason
for a \fBnotread\fR error in more detail\&.
.RE
.RE
.IP [5]
A plugin has to provide one command, with the signature shown
below\&.
.RS
.TP
\fBimport\fR \fItext\fR \fIconfiguration\fR
Whenever an import manager of \fBdoctools::toc\fR has to parse
input for a table of contents it will invoke this command\&.
.RS
.TP
string \fItext\fR
This argument will contain the text encoding the table of contents per
the format the plugin is for\&.
.TP
dictionary \fIconfiguration\fR
This argument will contain the current configuration to apply to the
parsing, as a dictionary mapping from variable names to values\&.
.sp
The following configuration variables have a predefined meaning all
plugins have to obey, although they can ignore this information at
their discretion\&. Any other other configuration variables recognized
by a plugin will be described in the manpage for that plugin\&.
.RS
.TP
user
This variable is expected to contain the name of the user
owning the process invoking the plugin\&.
.TP
format
This variable is expected to contain the name of the
format whose plugin is invoked\&.
.RE
.RE
.RE
.IP [6]
A single usage cycle of a plugin consists of the invokations of
the command \fBimport\fR\&. This call has to leave the plugin in
a state where another usage cycle can be run without problems\&.
.PP
.SH "TOC SERIALIZATION FORMAT"
Here we specify the format used by the doctools v2 packages to
serialize tables of contents as immutable values for transport,
comparison, etc\&.
.PP
We distinguish between \fIregular\fR and \fIcanonical\fR
serializations\&.
While a table of contents may have more than one regular serialization
only exactly one of them will be \fIcanonical\fR\&.
.PP
.TP
regular serialization
.RS
.IP [1]
The serialization of any table of contents is a nested Tcl dictionary\&.
.IP [2]
This dictionary holds a single key, \fBdoctools::toc\fR, and its
value\&. This value holds the contents of the table of contents\&.
.IP [3]
The contents of the table of contents are a Tcl dictionary holding the
title of the table of contents, a label, and its elements\&. The
relevant keys and their values are
.RS
.TP
\fBtitle\fR
The value is a string containing the title of the table of contents\&.
.TP
\fBlabel\fR
The value is a string containing a label for the table of contents\&.
.TP
\fBitems\fR
The value is a Tcl list holding the elements of the table, in the
order they are to be shown\&.
.sp
Each element is a Tcl list holding the type of the item, and its
description, in this order\&. An alternative description would be that
it is a Tcl dictionary holding a single key, the item type, mapped to
the item description\&.
.sp
The two legal item types and their descriptions are
.RS
.TP
\fBreference\fR
This item describes a single entry in the table of contents,
referencing a single document\&.
To this end its value is a Tcl dictionary containing an id for the
referenced document, a label, and a longer textual description which
can be associated with the entry\&.
The relevant keys and their values are
.RS
.TP
\fBid\fR
The value is a string containing the id of the document associated
with the entry\&.
.TP
\fBlabel\fR
The value is a string containing a label for this entry\&. This string
also identifies the entry, and no two entries (references and
divisions) in the containing list are allowed to have the same label\&.
.TP
\fBdesc\fR
The value is a string containing a longer description for this entry\&.
.RE
.TP
\fBdivision\fR
This item describes a group of entries in the table of contents,
inducing a hierarchy of entries\&.
To this end its value is a Tcl dictionary containing a label for the
group, an optional id to a document for the whole group, and the list
of entries in the group\&.
The relevant keys and their values are
.RS
.TP
\fBid\fR
The value is a string containing the id of the document associated
with the whole group\&. This key is optional\&.
.TP
\fBlabel\fR
The value is a string containing a label for the group\&. This string
also identifies the entry, and no two entries (references and
divisions) in the containing list are allowed to have the same label\&.
.TP
\fBitems\fR
The value is a Tcl list holding the elements of the group, in the
order they are to be shown\&.
This list has the same structure as the value for the keyword
\fBitems\fR used to describe the whole table of contents, see
above\&. This closes the recusrive definition of the structure, with
divisions holding the same type of elements as the whole table of
contents, including other divisions\&.
.RE
.RE
.RE
.RE
.TP
canonical serialization
The canonical serialization of a table of contents 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 this table of contents\&.
.RS
.IP [1]
The keys found in all the nested Tcl dictionaries are sorted in
ascending dictionary order, as generated by Tcl's builtin command
\fBlsort -increasing -dict\fR\&.
.RE
.PP
.SH "BUGS, IDEAS, FEEDBACK"
This document, and the package it describes, will undoubtedly contain
bugs and other problems\&.
Please report such in the category \fIdoctools\fR of the
\fITcllib Trackers\fR [http://core\&.tcl\&.tk/tcllib/reportlist]\&.
Please also report any ideas for enhancements you may have for either
package and/or documentation\&.
.SH KEYWORDS
conversion, doctoc, documentation, import, json, manpage, markup, parsing, plugin, reference, table, table of contents, url
.SH CATEGORY
Documentation tools
.SH COPYRIGHT
.nf
Copyright (c) 2009 Andreas Kupries <andreas_kupries@users\&.sourceforge\&.net>

.fi