org.extex.unit.omega.ocp
Class Nullocplist

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.unit.omega.ocp.Nullocplist

All Implemented Interfaces:

java.io.Serializable, Code, Showable, OcplistConvertible

public class Nullocplist
extends AbstractCode
implements Showable, OcplistConvertible

This class provides an implementation for the primitive \nullocplist.

The Primitive \nullocplist

The primitive \nullocplist can be used to build up an ΩPC list. It is valid in the context of the primitive \ocplist only.

Syntax

The formal description of this primitive is the following:

    ⟨nullocplist⟩
      → \nullocplist  

Examples

 \nullocplist 

Version:

$Revision: 4732 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Constructor Summary

Nullocplist(CodeToken token)
Creates a new object.

Method Summary

OcpList	convertOcplist(Context context, TokenSource source, Typesetter typesetter) Convert the value into an ΩPC list.
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.
Tokens	show(Context context) This method is the getter for the description of the primitive.

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

Constructor Detail

Nullocplist

public Nullocplist(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)

show

public Tokens show(Context context)
            throws HelpingException

This method is the getter for the description of the primitive.

Specified by:

show in interface Showable

Parameters:

context - the interpreter context

Returns:

the description of the primitive as list of Tokens

Throws:

HelpingException - in case of an error

See Also:

Showable.show( org.extex.interpreter.context.Context)

convertOcplist

public OcpList convertOcplist(Context context,
                              TokenSource source,
                              Typesetter typesetter)
                       throws HelpingException

Convert the value into an ΩPC list. Some tokens may be read from the input stream to perform the job.

Specified by:

convertOcplist in interface OcplistConvertible

Parameters:

context - the interpreter context

source - the source for new tokens

typesetter - the typesetter

Returns:

the ΩPC list encountered

Throws:

HelpingException - in case of an error

See Also:

OcplistConvertible.convertOcplist( org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)