org.extex.unit.tex.macro
Class Futurelet

java.lang.Object
  extended by org.extex.interpreter.type.AbstractCode
      extended by org.extex.interpreter.type.AbstractAssignment
          extended by org.extex.unit.tex.macro.Let
              extended by org.extex.unit.tex.macro.Futurelet
All Implemented Interfaces:
java.io.Serializable, Code

public class Futurelet
extends Let

This class provides an implementation for the primitive \futurelet.

The Primitive \futurelet

The primitive \futurelet lets a token to a control sequence while keeping the token between the two out of sight. This means that this token is stored away and reinserted after the let is complete.

Syntax

The formal description of this primitive is the following:
    ⟨futurelet⟩
      → \futurelet ⟨control sequence⟩ ⟨token⟩ ⟨token⟩  

Examples

    \futurelet \aa\bb x  

Version:
$Revision: 4770 $
Author:
Gerd Neugebauer
See Also:
Serialized Form

Field Summary
protected static long serialVersionUID
          The constant serialVersionUID contains the id for serialization.
 
Constructor Summary
Futurelet(CodeToken token)
          Creates a new object.
 
Method Summary
 void assign(Flags prefix, Context context, TokenSource source, Typesetter typesetter)
          The method assign is the core of the functionality of execute(). This method is preferable to execute() since the execute() method provided in this class takes care of \afterassignment and \globaldefs as well.
 
Methods inherited from class org.extex.unit.tex.macro.Let
let
 
Methods inherited from class org.extex.interpreter.type.AbstractAssignment
execute
 
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

Futurelet

public Futurelet(CodeToken token)
Creates a new object.

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

assign

public void assign(Flags prefix,
                   Context context,
                   TokenSource source,
                   Typesetter typesetter)
            throws HelpingException,
                   TypesetterException
The method assign is the core of the functionality of execute(). This method is preferable to execute() since the execute() method provided in this class takes care of \afterassignment and \globaldefs as well.

Overrides:
assign in class Let
Parameters:
prefix - the prefix controlling the execution
context - the interpreter context
source - the token source
typesetter - the typesetter
Throws:
HelpingException - in case of an error
TypesetterException - in case of an error in the typesetter
See Also:
Let.assign(org.extex.interpreter.Flags, org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)