@node Texinfo::Common
@chapter Texinfo::Common

@menu
* Texinfo@asis{::}Common NAME::
* Texinfo@asis{::}Common SYNOPSIS::
* Texinfo@asis{::}Common DESCRIPTION::
* Texinfo@asis{::}Common COMMAND CLASSES::
* Texinfo@asis{::}Common METHODS::
* Texinfo@asis{::}Common SEE ALSO::
* Texinfo@asis{::}Common AUTHOR::
@end menu

@node Texinfo::Common NAME
@section NAME

Texinfo::Common - Classification of commands and miscellaneous methods

@node Texinfo::Common SYNOPSIS
@section SYNOPSIS

@verbatim
  use Texinfo::Common qw(expand_today expand_verbatiminclude);
  if ($Texinfo::Common::accent_commands{$a_command}) {
    print STDERR "$a_command is an accent command\n";
  }
  
  my $today_tree = expand_today($converter);
  my $verbatiminclude_tree 
     = expand_verbatiminclude(undef, $verbatiminclude);
@end verbatim

@node Texinfo::Common DESCRIPTION
@section DESCRIPTION

Texinfo::Common holds interesting hashes classifying Texinfo @@-commands,
as well as miscellaneous methods that may be useful for any backend
converting texinfo trees.

It also defines, as our variable a hash for default indices,
named @code{%index_names}.  The format of this hash is described in 
@ref{Texinfo::Parser indices_information}.

@node Texinfo::Common COMMAND CLASSES
@section COMMAND CLASSES

Hashes are defined as @code{our} variables, and are therefore available
outside of the module.

The key of the hashes are @@-command names without the @@.  The 
following hashes are available:

@table @asis
@item %all_commands
@anchor{Texinfo::Common %all_commands}

All the @@-commands.

@item %no_brace_commands
@anchor{Texinfo::Common %no_brace_commands}

Commands without brace with a single character as name, like @code{*}
or @code{:}.  The value is an ascii representation of the command.  It
may be an empty string.

@item %misc_commands
@anchor{Texinfo::Common %misc_commands}

Command that do not take braces and are not block commands either, like
@code{@@node}, @code{@@chapter}, @code{@@cindex}, @code{@@deffnx}, @code{@@end}, @code{@@footnotestyle}, 
@code{@@set}, @code{@@settitle}, @code{@@indent}, @code{@@definfoenclose}, @code{@@comment} and many 
others.

@item %default_index_commands
@anchor{Texinfo::Common %default_index_commands}

Index entry commands corresponding to default indices. For example 
@code{@@cindex}.

@item %root_commands
@anchor{Texinfo::Common %root_commands}

Commands that are at the root of a Texinfo document, namely
@code{@@node} and sectioning commands, except heading commands.

@item %sectioning_commands
@anchor{Texinfo::Common %sectioning_commands}

All the sectioning and heading commands.

@item %brace_commands
@anchor{Texinfo::Common %brace_commands}

The commands that take braces.  The associated value is the maximum
number of arguments.

@item %letter_no_arg_commands
@anchor{Texinfo::Common %letter_no_arg_commands}

@@-commands with braces but no argument corresponding to letters, 
like @code{@@AA@{@}} or @code{@@ss@{@}} or @code{@@o@{@}}.

@item %accent_commands
@anchor{Texinfo::Common %accent_commands}

Accent @@-commands taking an argument, like @code{@@'} or @code{@@ringaccent} 
including @code{@@dotless} and @code{@@tieaccent}.

@item %style_commands
@anchor{Texinfo::Common %style_commands}

Commands that mark a fragment of texinfo, like @code{@@strong},
@code{@@cite}, @code{@@code} or @code{@@asis}.

@item %code_style_commands
@anchor{Texinfo::Common %code_style_commands}

@emph{style_commands} that have their argument in code style, like 
@code{@@code}.

@item %regular_font_style_commands
@anchor{Texinfo::Common %regular_font_style_commands}

@emph{style_commands} that have their argument in regular font, like
@code{@@r} or @code{@@slanted}.

@item %context_brace_commands
@anchor{Texinfo::Common %context_brace_commands}

@@-commands with brace like @code{@@footnote}, @code{@@caption} and @code{@@math}
whose argument is outside of the main text flow in one way or another.

@item %ref_commands
@anchor{Texinfo::Common %ref_commands}

Cross reference @@-command referencing nodes, like @code{@@xref}.

@item %explained_commands
@anchor{Texinfo::Common %explained_commands}

@@-commands whose second argument explain first argument and further
@@-command call without first argument, as @code{@@abbr} and @code{@@acronym}.

@item %block commands
@anchor{Texinfo::Common %block commands}

Commands delimiting a block with a closing @code{@@end}.  The value
is @emph{conditional} for @code{@@if} commands, @emph{def} for definition
commands like @code{@@deffn}, @emph{raw} for @@-commands that have no expansion
of @@-commands in their bodies and @emph{multitable} for @code{@@multitable}.  
Otherwise it is set to the number of arguments separated by commas 
that may appear on the @@-command line. That means 0 in most cases, 
1 for @code{@@quotation} and 2 for @code{@@float}.

@item %raw_commands
@anchor{Texinfo::Common %raw_commands}

@@-commands that have no expansion of @@-commands in their bodies,
as @code{@@macro}, @code{@@verbatim} or @code{@@ignore}.

@item %format_raw_commands
@anchor{Texinfo::Common %format_raw_commands}

@@-commands associated with raw output format, like @code{@@html}, or
@code{@@docbook}.

@item %math_commands
@anchor{Texinfo::Common %math_commands}

@@-commands which contains math, like @code{@@math} or @code{@@displaymath}.

@item %texinfo_output_formats
@anchor{Texinfo::Common %texinfo_output_formats}

Cannonical output formats that have associated conditionals.  In
practice @code{%format_raw_commands} plus @code{info} and @code{plaintext}.

@item %def_commands
@anchor{Texinfo::Common %def_commands}

@item %def_aliases
@anchor{Texinfo::Common %def_aliases}

Definition commands.  @code{%def_aliases} associates an aliased command
to the original command, for example @code{defun} is associated to @code{deffn}.

@item %menu_commands
@anchor{Texinfo::Common %menu_commands}

@@-commands with menu entries.

@item %align_commands
@anchor{Texinfo::Common %align_commands}

@@-commands related with alignement of text.

@item %region_commands
@anchor{Texinfo::Common %region_commands}

Block @@-commands that enclose full text regions, like @code{@@titlepage}.

@item %preformatted_commands
@anchor{Texinfo::Common %preformatted_commands}

@item %preformatted_code_commands
@anchor{Texinfo::Common %preformatted_code_commands}

@emph{%preformatted_commands} is for commands whose content should not 
be filled, like @code{@@example} or @code{@@display}.  If the command is meant 
for code, it is also in @emph{%preformatted_code_commands}, like @code{@@example}.

@item %item_container_commands
@anchor{Texinfo::Common %item_container_commands}

Commands holding @code{@@item} with @code{@@item} that contains blocks of text, 
like @code{@@itemize}.

@item %item_line_commands
@anchor{Texinfo::Common %item_line_commands}

Commands with @code{@@item} that have their arguments on their lines, like
@code{@@ftable}.

@end table

@node Texinfo::Common METHODS
@section METHODS

No method is exported in the default case.

Most methods takes a @emph{$converter} as argument, sometime optionally, 
to get some information and use methods for error reporting, 
see @ref{Texinfo::Convert::Converter NAME} and @ref{Texinfo::Report NAME}.

@table @asis
@item $tree = expand_today($converter)
@anchor{Texinfo::Common $tree = expand_today($converter)}

Expand today's date, as a texinfo tree with translations.

@item $tree = expand_verbatiminclude($converter, $verbatiminclude)
@anchor{Texinfo::Common $tree = expand_verbatiminclude($converter@comma{} $verbatiminclude)}

The @emph{$converter} argument may be undef.  @emph{$verbatiminclude} is a
@code{@@verbatiminclude} tree element.  This function returns a 
@code{@@verbatim} tree elements after finding the included file and
reading it.  If @emph{$converter} is not defined, the document encoding 
is not taken into account when reading the file.

@item $tree = definition_category($converter, $def_line)
@anchor{Texinfo::Common $tree = definition_category($converter@comma{} $def_line)}

The @emph{$converter} argument may be undef.  @emph{$def_line} is a 
@code{def_line} texinfo tree container.  This function
returns a texinfo tree corresponding to the category of the
@emph{$def_line} taking the class into account, if there is one.
If @emph{$converter} is not defined, the resulting string won't be
translated.

@item $result = is_content_empty($tree, $do_not_ignore_index_entries)
@anchor{Texinfo::Common $result = is_content_empty($tree@comma{} $do_not_ignore_index_entries)}

Return true if the @code{$tree} has content that could be formatted.
@code{$do_not_ignore_index_entries} is optional.  If set, index entries
are considered to be formatted.

@item $result = numbered_heading ($converter, $heading_element, $heading_text, $do_number)
@anchor{Texinfo::Common $result = numbered_heading ($converter@comma{} $heading_element@comma{} $heading_text@comma{} $do_number)}

The @emph{$converter} argument may be undef.  @emph{$heading_element} is 
a heading command tree element.  @emph{$heading_text} is the already 
formatted heading text.  if the @emph{$do_number} optional argument is 
defined and false, no number is used and the text is returned as is.
This function returns the heading with a number and the appendix 
part if needed.  If @emph{$converter} is not defined, the resulting 
string won't be translated.

@item ($caption, $prepended) = float_name_caption ($converter, $float)
@anchor{Texinfo::Common ($caption@comma{} $prepended) = float_name_caption ($converter@comma{} $float)}

@emph{$float} is a texinfo tree @code{@@float} element.  This function 
returns the caption that should be used for the float formatting 
and the @emph{$prepended} texinfo tree combining the type and label
of the float.

@item $text = enumerate_item_representation($specification, $number)
@anchor{Texinfo::Common $text = enumerate_item_representation($specification@comma{} $number)}

This function returns the number or letter correponding to item
number @emph{$number} for an @code{@@enumerate} specification @emph{$specification},
appearing on an @code{@@enumerate} line.  For example

@verbatim
  enumerate_item_representation('c', 3)
@end verbatim

is @code{e}.

@item trim_spaces_comment_from_content($contents)
@anchor{Texinfo::Common trim_spaces_comment_from_content($contents)}

Remove empty spaces after commands or braces at begin and
spaces and comments at end from a content array, modifying it.

@item $normalized_name = normalize_top_node_name ($node_string)
@anchor{Texinfo::Common $normalized_name = normalize_top_node_name ($node_string)}

Normalize the node name string given in argument, by normalizing
Top node case.

@item protect_comma_in_tree($tree)
@anchor{Texinfo::Common protect_comma_in_tree($tree)}

Protect comma characters, replacing @code{,} with @@comma@{@} in tree.

@item protect_colon_in_tree($tree)
@anchor{Texinfo::Common protect_colon_in_tree($tree)}

@item protect_node_after_label_in_tree($tree)
@anchor{Texinfo::Common protect_node_after_label_in_tree($tree)}

Protect colon with @code{protect_colon_in_tree} and characters that 
are special in node names after a label in menu entries (tab
dot and comma) with @code{protect_node_after_label_in_tree}.  
The protection is achieved by putting protected characters 
in @code{@@asis@{@}}.

@item $contents_result = protect_first_parenthesis ($contents)
@anchor{Texinfo::Common $contents_result = protect_first_parenthesis ($contents)}

Return a contents array reference with first parenthesis in the 
contents array reference protected.

@item protect_hashchar_at_line_beginning($parser, $tree)
@anchor{Texinfo::Common protect_hashchar_at_line_beginning($parser@comma{} $tree)}

Protect hash character at beginning of line if the line is a cpp
line directive.  The @emph{$parser} argument maybe undef, if it is 
defined it is used for error reporting in case an hash character
could not be protected because it appeared in a raw environment.

@item move_index_entries_after_items_in_tree($tree)
@anchor{Texinfo::Common move_index_entries_after_items_in_tree($tree)}

In @code{@@enumerate} and @code{@@itemize} from the tree, move index entries 
appearing just before @code{@@item} after the @code{@@item}.  Comment lines 
between index entries are moved too.

@item $command = find_parent_root_command($parser, $tree_element)
@anchor{Texinfo::Common $command = find_parent_root_command($parser@comma{} $tree_element)}

Find the parent root command of a tree element (sectioning command or node).
The @code{$parser} argument is optional, it is used to continue 
through @code{@@insertcopying} if in a @code{@@copying}.

@item valid_tree_transformation($name)
@anchor{Texinfo::Common valid_tree_transformation($name)}

Return true if the @emph{$name} is a known tree transformation name
that may be passed with @code{TREE_TRANSFORMATIONS} to modify a texinfo
tree.

@item collect_commands_in_tree($tree, $commands_list)
@anchor{Texinfo::Common collect_commands_in_tree($tree@comma{} $commands_list)}

Returns a hash reference with keys @@-commands names specified
in the @emph{$commands_list} array reference and values arrays of
tree elements corresponding to those @@-command found in @emph{$tree}
by traversing the tree.

@end table

@node Texinfo::Common SEE ALSO
@section SEE ALSO

@ref{Texinfo::Parser NAME}, @ref{Texinfo::Convert::Converter NAME} and @ref{Texinfo::Report NAME}. 

@node Texinfo::Common AUTHOR
@section AUTHOR

Patrice Dumas, <pertusus@@free.fr>

