io.parsingdata.metal.token

Class Pre

java.lang.Object

io.parsingdata.metal.token.Token

io.parsingdata.metal.token.Pre

public class Pre
extends Token

A Token that specifies a conditional token.

A Pre consists of a token (a Token) and a predicate (an Expression). First predicate is evaluated. If it evaluates to true, the token is parsed. The only way for Pre to fail is if predicate evaluates to true, but parsing the token fails.

See Also:

Expression

Field Summary

Fields

Modifier and Type	Field and Description
Expression	predicate
Token	token

Fields inherited from class io.parsingdata.metal.token.Token

encoding, name, NO_NAME, SEPARATOR

Constructor Summary

Constructors

Constructor and Description
Pre(String name, Token token, Expression predicate, Encoding encoding)

Method Summary

Modifier and Type	Method and Description
protected ParseResult	parseImpl(String scope, Environment environment, Encoding encoding)
String	toString()

Methods inherited from class io.parsingdata.metal.token.Token

getCanonical, isLocal, makeNameFragment, parse, parse

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

token

public final Token token

predicate

public final Expression predicate

Constructor Detail

Pre

public Pre(String name,
           Token token,
           Expression predicate,
           Encoding encoding)

Method Detail

parseImpl

protected ParseResult parseImpl(String scope,
                                Environment environment,
                                Encoding encoding)
                         throws IOException

Specified by:

parseImpl in class Token

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object