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doctools::idx::export::nroff - Documentation tools
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doctools::idx::export::nroff(n) 0.3 tcllib "Documentation tools"


doctools::idx::export::nroff - nroff export plugin


  • package require Tcl 8.4
  • package require doctools::idx::export::nroff ?0.3?
  • package require doctools::text
  • package require doctools::nroff::man_macros


This package implements the doctools keyword index export plugin for the generation of nroff markup.

This is an internal package of doctools, for use by the higher level management packages handling keyword indices, especially doctools::idx::export, the export manager.

Using it from a regular interpreter is possible, however only with contortions, and is not recommended. The proper way to use this functionality is through the package doctools::idx::export and the export manager objects it provides.


The API provided by this package satisfies the specification of the docidx export plugin API version 2.

export serial configuration

This command takes the canonical serialization of a keyword index, as specified in section Keyword index serialization format, and contained in serial, the configuration, a dictionary, and generates nroff markup encoding the index. The created string is then returned as the result of the command.


The nroff export plugin recognizes the following configuration variables and changes its behaviour as they specify.

string user

This standard configuration variable contains the name of the user running the process which invoked the export plugin. The plugin puts this information into the provenance comment at the beginning of the generated document.

string file

This standard configuration variable contains the name of the file the index came from. This variable may not be set or contain the empty string. The plugin puts this information, if defined, i.e. set and not the empty string, into the provenance comment at the beginning of the generated document.

boolean inline

If this flag is set (default) the plugin will place the definitions of the man macro set directly into the output.

If this flag is not set, the plugin will place a reference to the definitions of the man macro set into the output, but not the macro definitions themselves.

Note that this plugin ignores the standard configuration variables format, and map, and their values.

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


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


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


    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.


    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,


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


    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. 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.


Text formatter plugin