NAME

LaTeXML::Core::State - stores the current state of processing.

DESCRIPTION

A LaTeXML::Core::State object stores the current state of processing. It recording catcodes, variables values, definitions and so forth, as well as mimicking TeX's scoping rules.

Access to State and Processing

$STATE->getStomach;

Returns the current Stomach used for digestion.

$STATE->getModel;

Returns the current Model representing the document model.

Scoping

The assignment methods, described below, generally take a $scope argument, which determines how the assignment is made. The allowed values and their implications are:

global   : global assignment.
local    : local assignment, within the current grouping.
undef    : global if \global preceded, else local (default)
<name>   : stores the assignment in a `scope' which
           can be loaded later.

If no scoping is specified, then the assignment will be global if a preceding \global has set the global flag, otherwise the value will be assigned within the current grouping.

$STATE->pushFrame;

Starts a new level of grouping. Note that this is lower level than \bgroup; See LaTeXML::Core::Stomach.

$STATE->popFrame;

Ends the current level of grouping. Note that this is lower level than \egroup; See LaTeXML::Core::Stomach.

$STATE->setPrefix($prefix);

Sets a prefix (eg. global for \global, etc) for the next operation, if applicable.

$STATE->clearPrefixes;

Clears any prefixes.

Values

$value = $STATE->lookupValue($name);

Lookup the current value associated with the the string $name.

$STATE->assignValue($name,$value,$scope);

Assign $value to be associated with the the string $name, according to the given scoping rule.

Values are also used to specify most configuration parameters (which can therefore also be scoped). The recognized configuration parameters are:

STRICT            : whether errors (eg. undefined macros)
                    are fatal.
INCLUDE_COMMENTS  : whether to preserve comments in the
                    source, and to add occasional line
                    number comments. (Default true).
PRESERVE_NEWLINES : whether newlines in the source should
                    be preserved (not 100% TeX-like).
                    By default this is true.
SEARCHPATHS       : a list of directories to search for
                    sources, implementations, etc.

$STATE->pushValue($name,$value);

This is like ->assign, but pushes a value onto the end of the stored value, which should be a LIST reference. Scoping is not handled here (yet?), it simply pushes the value onto the last binding of $name.

$boole = $STATE->isValuebound($type,$name,$frame);

Returns whether the value $name is bound. If $frame is given, check whether it is bound in the $frame-th frame, with 0 being the top frame.

Category Codes

$value = $STATE->lookupCatcode($char);

Lookup the current catcode associated with the the character $char.

$STATE->assignCatcode($char,$catcode,$scope);

Set $char to have the given $catcode, with the assignment made according to the given scoping rule.

This method is also used to specify whether a given character is active in math mode, by using math:$char for the character, and using a value of 1 to specify that it is active.

Definitions

$defn = $STATE->lookupMeaning($token);

Get the "meaning" currently associated with $token, either the definition (if it is a control sequence or active character) or the token itself if it shouldn't be executable. (See LaTeXML::Core::Definition)

$STATE->assignMeaning($token,$defn,$scope);

Set the definition associated with $token to $defn. If $globally is true, it makes this the global definition rather than bound within the current group. (See LaTeXML::Core::Definition, and LaTeXML::Package)

$STATE->installDefinition($definition, $scope);

Install the definition into the current stack frame under its normal control sequence.

Named Scopes

Named scopes can be used to set variables or redefine control sequences within a scope other than the standard TeX grouping. For example, the LaTeX implementation will automatically activate any definitions that were defined with a named scope of, say "section:4", during the portion of the document that has the section counter equal to 4. Similarly, a scope named "label:foo" will be activated in portions of the document where \label{foo} is in effect.

$STATE->activateScope($scope);

Installs any definitions that were associated with the named $scope. Note that these are placed in the current grouping frame and will disappear when that grouping ends.

$STATE->deactivateScope($scope);

Removes any definitions that were associated with the named $scope. Normally not needed, since a scopes definitions are locally bound anyway.

$sp = $STATE->convertUnit($unit);

Converts a TeX unit of the form '10em' (or whatever TeX unit) into scaled points. (Defined here since in principle it could track the size of ems and so forth (but currently doesn't))

AUTHOR

Bruce Miller <bruce.miller@nist.gov>

COPYRIGHT

Public domain software, produced as part of work done by the United States Government & not subject to copyright in the US.