org.extex.unit.tex.prefix
Class Global

java.lang.Object
  extended by org.extex.interpreter.type.AbstractCode
      extended by org.extex.unit.tex.prefix.Global
All Implemented Interfaces:
java.io.Serializable, Code, PrefixCode

public class Global
extends AbstractCode
implements PrefixCode

This class provides an implementation for the primitive \global. It does simply nothing, but as a side effect the prefix GLOBAL is added to the prefixes.

The Prefix Primitive \global

The primitive \global is a prefix macro. It does not do anything by its own but works in combination with a following primitive token only. If the following token constitutes an assignment then the assignment is not restricted to the current group but acts globally in all groups.

If the following command token does not happen to be an operation for which the global modifier is applicable then a warning might be raised.

Multiple \global prefixes act identical to a single one.

Syntax

The formal description of this primitive is the following:

   ⟨global⟩
     → \global  

Examples

The following example shows that two macros defined in a group. The first macro falls back to its previous binding when the group is closed. The second macro has the same binding in all groups. defined.

   \begingroup
     \def\a{123}
     \global\def\b{123}
   \endgroup  

The following example shows that two count registers are set in a group. The first count register keeps its value untile the group is closed and falls back to the value it had when the group has been entered. The second count register keeps its value even when the group is closed.

   \begingroup
     \count1=123
     \global\count2=45
   \endgroup  

Version:
$Revision:4431 $
Author:
Gerd Neugebauer
See Also:
Serialized Form

Field Summary
protected static long serialVersionUID
          The constant serialVersionUID contains the id for serialization.
 
Constructor Summary
Global(CodeToken token)
          Creates a new object.
 
Method Summary
 void execute(Flags prefix, Context context, TokenSource source, Typesetter typesetter)
          This method takes the first token and executes it. The result is placed on the stack. This operation might have side effects. To execute a token it might be necessary to consume further tokens.
 
Methods inherited from class org.extex.interpreter.type.AbstractCode
getLocalizer, getName, getToken, isIf, isOuter, readResolve, toString, toText, toText
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

serialVersionUID

protected static final long serialVersionUID
The constant serialVersionUID contains the id for serialization.

See Also:
Constant Field Values
Constructor Detail

Global

public Global(CodeToken token)
Creates a new object.

Parameters:
token - the initial token for the primitive
Method Detail

execute

public void execute(Flags prefix,
                    Context context,
                    TokenSource source,
                    Typesetter typesetter)
This method takes the first token and executes it. The result is placed on the stack. This operation might have side effects. To execute a token it might be necessary to consume further tokens.

Specified by:
execute in interface Code
Overrides:
execute in class AbstractCode
Parameters:
prefix - the prefix controlling the execution
context - the interpreter context
source - the token source
typesetter - the typesetter
See Also:
AbstractCode.execute( org.extex.interpreter.Flags, org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)