Class Ifx

  extended byde.dante.extex.interpreter.type.AbstractCode
      extended byde.dante.extex.interpreter.primitives.conditional.AbstractIf
          extended byde.dante.extex.interpreter.primitives.conditional.Ifx
All Implemented Interfaces:
Code, ExpandableCode, Localizable,

public class Ifx
extends AbstractIf

This class provides an implementation for the primitive \ifx.

The Primitive \ifx

The primitive \ifx compares the following two tokens. If the following tokens are no macros then the comparison succeeds if they agree in category code and character.

If the argument tokens are control sequences or active characters then the assigned values are compared. If the arguments are bound to macros then the comparison succeeds if the status of outer and long are the same, the patterns are the same and the body texts are equivalent

TODO missing documentation


The formal description of this primitive is the following:
      → \ifx ⟨token1 ⟨token2; ⟨true text⟩ \fi
      | \ifx ⟨token1 ⟨token2 ⟨true text⟩ \else ⟨false text⟩ \fi 


    \ifx\a\x ok \fi  

$Revision: 1.28 $
Gerd Neugebauer
See Also:
Serialized Form

Field Summary
protected static long serialVersionUID
          The constant serialVersionUID contains the id for serialization.
Constructor Summary
Ifx(java.lang.String name)
          Creates a new object.
Method Summary
protected  boolean conditional(Context context, TokenSource source, Typesetter typesetter)
          This method computes the boolean value of the conditional.
Methods inherited from class de.dante.extex.interpreter.primitives.conditional.AbstractIf
execute, expand, getMyLocalizer, isIf, skipToElseOrFi
Methods inherited from class de.dante.extex.interpreter.type.AbstractCode
enableLocalization, getLocalizer, getName, isOuter, printable, printableControlSequence, readResolve, setName, toString
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail


protected static final long serialVersionUID
The constant serialVersionUID contains the id for serialization.

See Also:
Constant Field Values
Constructor Detail


public Ifx(java.lang.String name)
Creates a new object.

name - the name for debugging
Method Detail


protected boolean conditional(Context context,
                              TokenSource source,
                              Typesetter typesetter)
                       throws InterpreterException
Description copied from class: AbstractIf
This method computes the boolean value of the conditional. If the result is true then the then branch is expanded and the else branch is skipped. Otherwise the then branch is skipped and the else branch is expanded.

Specified by:
conditional in class AbstractIf
context - the interpreter context
source - the source for new tokens
typesetter - the typesetter
the boolean value
InterpreterException - in case of en error
See Also:
AbstractIf.conditional( de.dante.extex.interpreter.context.Context, de.dante.extex.interpreter.TokenSource, de.dante.extex.typesetter.Typesetter)