org.extex.unit.tex.macro
Class Let

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.interpreter.type.AbstractAssignment
          org.extex.unit.tex.macro.Let

All Implemented Interfaces:

java.io.Serializable, Code

Direct Known Subclasses:

Futurelet, Import

public class Let
extends AbstractAssignment

This class provides an implementation for the primitive \let.

The Primitive \let

The primitive \let defined a control sequence or active character. The value is taken from the meaning of another token. If the token is a control sequence or active character then the meaning is used. If the other definition is changed the newly defined binding remains intact.

Syntax

The formal description of this primitive is the following:

    ⟨let⟩
      → \let ⟨control sequence⟩ ⟨equals⟩ ⟨token⟩  

Examples

    \let\a=\b  

Version:

$Revision: 4770 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Field Summary

protected static long

serialVersionUID The constant serialVersionUID contains the id for serialization.

Constructor Summary

Let(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().
static void	let(Flags prefix, Context context, CodeToken cs, Token t) Assign a new meaning to a control sequence.

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 constant serialVersionUID contains the id for serialization.

See Also:

Constant Field Values

Constructor Detail

Let

public Let(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:

HelpingException - in case of an error

TypesetterException - in case of an error in the typesetter

See Also:

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

let

public static void let(Flags prefix,
                       Context context,
                       CodeToken cs,
                       Token t)
                throws HelpingException

Assign a new meaning to a control sequence. This is the core of the primitive \let.

Parameters:

prefix - the flags to consider

context - the processor context

cs - the control sequence token to bind

t - the new meaning of the control sequence token. If this parameter is null then an exception is thrown.

Throws:

HelpingException - in case of an error