org.extex.unit.color
Class Colordef

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.interpreter.type.AbstractAssignment
          org.extex.unit.color.Colordef

All Implemented Interfaces:

java.io.Serializable, Code

public class Colordef
extends AbstractAssignment

This class provides an implementation for the primitive \colordef.

The Primitive \colordef

The primitive \colordef defines a color variable and assigns it to a control sequence. The color is initialized with a given color – either a color constant or a color variable.

The control sequence can later be used wherever a color is expected.

The primitive \colordef constitutes an assignment. Thus the count register \globaldefs and the token register \afterassignment interact with it as for each assignment.

The primitive can be prefixed with the \global flag. In this case the definition is performed globally. Otherwise the control sequence holds the color value in the current group only. It is reset to the previous value when the group is ended.

The color variable can be manipulated by assigning new colors to it. The assignment is accomplished by specifying the new value after an optional equals sign. Note that the assignment can not be prefixed by a \global modifier since the scope has already been specified in the declaration with \colordef.

Syntax

The formal description of this primitive is the following:

    ⟨colordef⟩
      → ⟨optional prefix⟩ \colordef ⟨control sequence⟩ ⟨color⟩

    ⟨optional prefix⟩
      →
       |  \global   

Examples

    \colordef\col alpha .1234 rgb {.2 .3 .4}  

    \global\colordef\col\color  

Version:

$Revision: 6447 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Field Summary

protected static long

serialVersionUID The field serialVersionUID contains the version number for serialization.

Constructor Summary

Colordef(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().

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 field serialVersionUID contains the version number for serialization.

See Also:

Constant Field Values

Constructor Detail

Colordef

public Colordef(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.

Specified by:

assign in class AbstractAssignment

Parameters:

prefix - the prefix controlling the execution

context - the interpreter context

source - the token source

typesetter - the typesetter

Throws:

org.extex.framework.configuration.exception.ConfigurationException - in case of an configuration error

HelpingException - in case of an error

TypesetterException - in case of an error in the typesetter

See Also:

AbstractAssignment.assign( org.extex.interpreter.Flags, org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)