org.extex.unit.tex.register.toks
Class ToksPrimitive

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.interpreter.type.AbstractAssignment
          org.extex.unit.base.register.toks.AbstractToks
              org.extex.unit.tex.register.toks.ToksPrimitive

All Implemented Interfaces:

java.io.Serializable, Code, Theable, TokensConvertible

public class ToksPrimitive
extends AbstractToks
implements TokensConvertible, Theable

This class provides an implementation for the primitive \toks. It sets the named tokens register to the value given, and as a side effect all prefixes are zeroed.

The Primitive \toks

The primitive \toks provides access to the named tokens register. token sequences can be stored in them for later use. This means that the tokens do not have to be parsed again. Even a change in the catcode settings does not alter the tokens build once.

The primitive \toks also respects the count register \globaldefs to enable general global assignment.

Since the primitive is classified as assignment the value of \afterassignment is applied.

Syntax

    ⟨toks⟩
      → \toks ⟨register name⟩ ⟨equals⟩ ⟨tokens⟩  

In TeX the register name is a number in the range 0 to 255. Extensions to this are defined in eTeX and Omega where the limitation of the range is raised. In ExTeX this limit can be configured. In addition tokens can be used to address named token registers.

Examples

    \toks2={UTF-8}  

    \toks42={UTF-8}  

    \toks42=\toks0  

    \toks{abc}={Hello world}  

Version:

$Revision:4431 $

Author:

Gerd Neugebauer, Michael Niedermair

See Also:

Serialized Form

serialVersionUID

protected static final long serialVersionUID

The constant serialVersionUID contains the id for serialization.

See Also:

Constant Field Values

ToksPrimitive

public ToksPrimitive(CodeToken token)

Creates a new object.

Parameters:

token - the initial token for the primitive

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:

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

convertTokens

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

This method converts a register into tokens. 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:

convertTokens in interface TokensConvertible

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:

TokensConvertible.convertTokens( org.extex.interpreter.context.Context, org.extex.interpreter.TokenSource, org.extex.typesetter.Typesetter)

the

public Tokens the(Context context,
                  TokenSource source,
                  Typesetter typesetter)
           throws 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:

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)