org.extex.unit.etex.conditional.analyze
Class Currentifbranch

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.unit.etex.conditional.analyze.Currentifbranch

All Implemented Interfaces:

java.io.Serializable, CountConvertible, Code, Theable

public class Currentifbranch
extends AbstractCode
implements CountConvertible, Theable

This class provides an implementation for the primitive \currentifbranch.

The Primitive \currentifbranch

The primitive \currentifbranch is an integer quantity which provides the information in which branch of the enclosing conditional. The value is determined by the following rules:

• If the then branch of the enclosing is active then the value is 1.
• If the else branch of the enclosing is active then the value is -1.
• If the enclosing conditional is \ifcase then the value is the number selecting the current case for normal cases and -1 for the else case.
• If there is no enclosing conditional then the value is 0.

The primitive \currentifbranch is a read-only quantity. an attempt to use this primitive in a horizontal or vertical mode results in an error.

Syntax

The formal description of this primitive is the following:

    ⟨currentifbranch⟩
     → \currentifbranch 

Examples

    \count0=\currentifbranch  

Version:

$Revision:4435 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Field Summary

protected static long

serialVersionUID The constant serialVersionUID contains the id for serialization.

Constructor Summary

Currentifbranch(CodeToken token)
Creates a new object.

Method Summary

long	convertCount(Context context, TokenSource source, Typesetter typesetter) This method converts a register into a count.
Tokens	the(Context context, TokenSource source, Typesetter typesetter) This method is the getter for the description of the primitive.

Methods inherited from class org.extex.interpreter.type.AbstractCode

execute, 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

Currentifbranch

public Currentifbranch(CodeToken token)

Creates a new object.

Parameters:

token - the initial token for the primitive

Method Detail

convertCount

public long convertCount(Context context,
                         TokenSource source,
                         Typesetter typesetter)
                  throws HelpingException,
                         TypesetterException

This method converts a register into a count. It might be necessary to read further tokens to determine which value to use. For instance an additional register number might be required. In this case the additional arguments Context and TokenSource can be used.

Specified by:

convertCount in interface CountConvertible

Parameters:

context - the interpreter context

source - the source for new tokens

typesetter - the typesetter to use for conversion

Returns:

the converted value

Throws:

HelpingException - in case of an error

TypesetterException - in case of an error in the typesetter

See Also:

CountConvertible.convertCount( org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)

the

public Tokens the(Context context,
                  TokenSource source,
                  Typesetter typesetter)
           throws CatcodeException,
                  HelpingException,
                  TypesetterException

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

Specified by:

the in interface Theable

Parameters:

context - the interpreter context

source - the source for further tokens to qualify the request

typesetter - the typesetter to use

Returns:

the description of the primitive as list of Tokens

Throws:

CatcodeException - in case of an error in token creation

ConfigurationException - in case of an configuration error

HelpingException - in case of an error

TypesetterException - in case of an error

See Also:

Theable.the( org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)