org.extex.unit.tex.typesetter.mark
Class AbstractMarksCode

java.lang.Object
  org.extex.interpreter.type.AbstractCode
      org.extex.unit.tex.typesetter.mark.AbstractMarksCode

All Implemented Interfaces:

java.io.Serializable, Code, ExpandableCode, TokensConvertible

Direct Known Subclasses:

Botmarks, Firstmarks, Splitbotmarks, Splitfirstmarks, Topmarks

public abstract class AbstractMarksCode
extends AbstractCode
implements ExpandableCode, TokensConvertible

Thus abstract base class for marks primitives provides the common features.

Version:

$Revision:4431 $

Author:

Gerd Neugebauer

See Also:

Serialized Form

Constructor Summary

AbstractMarksCode(CodeToken token)
Creates a new object.

Method Summary

Tokens	convertTokens(Context context, TokenSource source, Typesetter typesetter) This method converts a register into tokens.
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.
protected java.lang.String	getKey(Context context, TokenSource source, Typesetter typesetter) Get the key for this mark.
protected abstract Tokens	getValue(Context context, java.lang.String key) Get the value for this mark.

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

Constructor Detail

AbstractMarksCode

public AbstractMarksCode(CodeToken token)

Creates a new object.

Parameters:

token - the initial token for the primitive

Method Detail

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)

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 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:

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)

getKey

protected java.lang.String getKey(Context context,
                                  TokenSource source,
                                  Typesetter typesetter)
                           throws HelpingException,
                                  TypesetterException

Get the key for this mark.

A Mark Name

A mark name determines under which key a mark can be addressed. In TeX this used to be a positive number only. This has been extended to allow also a token list in braces.

The alternative is controlled by the count register \register.max. The following interpretation of the value of this count is used:

• If the value of this count register is negative then a arbitrary non-negative number is allowed as register name as well as any list of tokens enclosed in braces.
• If the value of this count register is not-negative then a only a non-negative number is allowed as register name which does not exceed the value of the count register.

The value of the count register \register.max is set differently for various configurations of ExTeX:

• TeX uses the value 255.
• eTeX uses the value 32767.
• Omega uses the value 65536.
• ExTeX uses the value -1.

Note that the register name \register.max contains a period. Thus it can normally not be entered easily since the catcode of the period is OTHER but needs to be LETTER. Thus you have to use a temporarily reassigned category code (see \catcode or use \csname.

Syntax

   ⟨register name⟩
       → ⟨tokens⟩
        | ⟨number⟩  

Examples

  123
  {abc}
 

Parameters:

context - the interpreter context

source - the source for new tokens

typesetter - the typesetter

Returns:

the key for the mark primitive

Throws:

HelpingException - in case of an error

TypesetterException - in case of an error in the typesetter

getValue

protected abstract Tokens getValue(Context context,
                                   java.lang.String key)

Get the value for this mark.

Parameters:

context - the interpreter context

key - the key

Returns:

the value