org.extex.unit.etex.scan
Class Scantokens

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.unit.etex.scan.Scantokens

All Implemented Interfaces:

java.io.Serializable, Code, ExpandableCode

public class Scantokens
extends AbstractCode
implements ExpandableCode

This class provides an implementation for the primitive \scantokens.

The Primitive \scantokens

The primitive \scantokens takes an unexpanded list of tokens and uses them as a new source for an input stream. For this purpose the tokens are translated into a string which is used as if it where written to a file and read back in.

The tokens from the tokens register \everyeof are inserted when the stream has no more tokens to read.

Syntax

The formal description of this primitive is the following:

    ⟨scantokens⟩
      → \scantokens ⟨tokens⟩  

Examples

    \scantokens{abc}  

Version:

$Revision:4435 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Field Summary

protected static long

serialVersionUID The field serialVersionUID contains the id for serialization.

Constructor Summary

Scantokens(CodeToken token)
Creates a new object.

Method Summary

void	execute(Flags prefix, Context context, TokenSource source, Typesetter typesetter) This method takes the first token and executes it. The result is placed on the stack. This operation might have side effects. To execute a token it might be necessary to consume further tokens.
void	expand(Flags prefix, Context context, TokenSource source, Typesetter typesetter) This method takes the first token and expands it.

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 id for serialization.

See Also:

Constant Field Values

Constructor Detail

Scantokens

public Scantokens(CodeToken token)

Creates a new object.

Parameters:

token - the initial token for the primitive

Method Detail

execute

public void execute(Flags prefix,
                    Context context,
                    TokenSource source,
                    Typesetter typesetter)
             throws HelpingException,
                    TypesetterException

This method takes the first token and executes it. The result is placed on the stack. This operation might have side effects. To execute a token it might be necessary to consume further tokens.

Specified by:

execute in interface Code

Overrides:

execute in class AbstractCode

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:

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

expand

public void expand(Flags prefix,
                   Context context,
                   TokenSource source,
                   Typesetter typesetter)
            throws ConfigurationException,
                   HelpingException,
                   TypesetterException

This method takes the first token and expands it. The result is placed on the stack. This means that expandable code does one step of expansion and puts the result on the stack. To expand a token it might be necessary to consume further tokens.

Specified by:

expand in interface ExpandableCode

Parameters:

prefix - the prefix flags controlling the expansion

context - the interpreter context

source - the token source

typesetter - the typesetter

Throws:

ConfigurationException - in case of an configuration error

HelpingException - in case of an error

TypesetterException - in case of an error in the typesetter

See Also:

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