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 mimicing 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 $scope argument, which
determines how the assignment is made. The allowed values and thier
implications are:
global : global assignment.
local : local assignment, within the current grouping.
undef : global if \global preceded, else local (default)
<name> : stores the assignment in a `scope' which
can be loaded later.
If no scoping is specified, then the assignment will be global if a preceding
"\global" has set the global flag, otherwise the value will be
assigned within the current grouping.
- "$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 $name, according to the
given scoping rule.
Values are also used to specify most configuration parameters (which can
therefor also be scoped). The recognized configuration parameters are:
VERBOSITY : the level of verbosity for debugging
output, with 0 being default.
STRICT : whether errors (eg. undefined macros)
are fatal.
INCLUDE_COMMENTS : whether to preserve comments in the
source, and to add occasional line
number comments. (Default true).
PRESERVE_NEWLINES : whether newlines in the source should
be preserved (not 100% TeX-like).
By default this is true.
SEARCHPATHS : a list of directories to search for
sources, implementations, etc.
- "$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.