org.extex.unit.tex.typesetter.undo
Class Unpenalty

java.lang.Object
  extended by org.extex.interpreter.type.AbstractCode
      extended by org.extex.unit.tex.typesetter.undo.Unpenalty
All Implemented Interfaces:
java.io.Serializable, Code

public class Unpenalty
extends AbstractCode

This class provides an implementation for the primitive \unpenalty.

The Primitive \unpenalty

The primitive \unpenalty inspects the current list and removes the last node if it is a penalty node. Otherwise an error is raised.

Syntax

The formal description of this primitive is the following:
    ⟨unpenalty⟩
        → \unpenalty  

Examples

    \unpenalty  

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
Unpenalty(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

Unpenalty

public Unpenalty(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)
             throws HelpingException,
                    TypesetterException
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
Throws:
HelpingException - in case of an error
TypesetterException - in case of an error in the typesetter
See Also:
AbstractCode.execute( org.extex.interpreter.Flags, org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)