org.sonar.sslr.grammar

Class LexerlessGrammarBuilder

java.lang.Object

org.sonar.sslr.grammar.LexerlessGrammarBuilder

public class LexerlessGrammarBuilder
extends Object

A builder for creating Parsing Expression Grammars for lexerless parsing.

Objects of following types can be used as an atomic parsing expressions:

• GrammarRuleKey
• String
• Character

Since:

1.18

See Also:

LexerfulGrammarBuilder

Method Summary

Modifier and Type	Method and Description
LexerlessGrammar	build() Constructs grammar.
Object	commentTrivia(Object e) Creates parsing expression - "comment trivia".
protected ParsingExpression	convertToExpression(Object e)
protected ParsingExpression[]	convertToExpressions(List<Object> expressions)
static LexerlessGrammarBuilder	create()
static LexerlessGrammarBuilder	createBasedOn(LexerlessGrammarBuilder... base)
Object	endOfInput() Creates parsing expression - "end of input".
Object	firstOf(Object e1, Object e2) Creates parsing expression - "first of".
Object	firstOf(Object e1, Object e2, Object... rest) Creates parsing expression - "first of".
Object	next(Object e) Creates parsing expression - "next".
Object	next(Object e1, Object... rest) Creates parsing expression - "next".
Object	nextNot(Object e) Creates parsing expression - "next not".
Object	nextNot(Object e1, Object... rest) Creates parsing expression - "next not".
Object	nothing() Creates parsing expression - "nothing".
Object	oneOrMore(Object e) Creates parsing expression - "one or more".
Object	oneOrMore(Object e1, Object... rest) Creates parsing expression - "one or more".
Object	optional(Object e) Creates parsing expression - "optional".
Object	optional(Object e1, Object... rest) Creates parsing expression - "optional".
Object	regexp(String regexp) Creates parsing expression based on regular expression.
GrammarRuleBuilder	rule(GrammarRuleKey ruleKey) Allows to describe rule.
Object	sequence(Object e1, Object e2) Creates parsing expression - "sequence".
Object	sequence(Object e1, Object e2, Object... rest) Creates parsing expression - "sequence".
void	setRootRule(GrammarRuleKey ruleKey) Allows to specify that given rule should be root for grammar.
Object	skippedTrivia(Object e) Creates parsing expression - "skipped trivia".
Object	token(TokenType tokenType, Object e) Creates parsing expression - "token".
Object	zeroOrMore(Object e) Creates parsing expression - "zero or more".
Object	zeroOrMore(Object e1, Object... rest) Creates parsing expression - "zero or more".

Methods inherited from class java.lang.Object

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

Method Detail

create

public static LexerlessGrammarBuilder create()

createBasedOn

public static LexerlessGrammarBuilder createBasedOn(LexerlessGrammarBuilder... base)

rule

public GrammarRuleBuilder rule(GrammarRuleKey ruleKey)

Allows to describe rule. Result of this method should be used only for execution of methods in it, i.e. you should not save reference on it. No guarantee that this method always returns the same instance for the same key of rule.

setRootRule

public void setRootRule(GrammarRuleKey ruleKey)

Allows to specify that given rule should be root for grammar.

build

public LexerlessGrammar build()

Constructs grammar.

Returns:

grammar

Throws:

GrammarException - if some of rules were used, but not defined

regexp

public Object regexp(String regexp)

Creates parsing expression based on regular expression.

Parameters:

regexp - regular expression

Throws:

PatternSyntaxException - if the expression's syntax is invalid

endOfInput

public Object endOfInput()

Creates parsing expression - "end of input". This expression succeeds only if parser reached end of input.

token

public Object token(TokenType tokenType,
                    Object e)

Creates parsing expression - "token".

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

commentTrivia

public Object commentTrivia(Object e)

Creates parsing expression - "comment trivia".

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

skippedTrivia

public Object skippedTrivia(Object e)

Creates parsing expression - "skipped trivia".

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

convertToExpression

protected ParsingExpression convertToExpression(Object e)

sequence

public final Object sequence(Object e1,
                             Object e2)

Creates parsing expression - "sequence". During execution of this expression parser will sequentially execute all sub-expressions. This expression succeeds only if all sub-expressions succeed.

Parameters:

e1 - first sub-expression

e2 - second sub-expression

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

sequence

public final Object sequence(Object e1,
                             Object e2,
                             Object... rest)

Creates parsing expression - "sequence". See sequence(Object, Object) for more details.

Parameters:

e1 - first sub-expression

e2 - second sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

firstOf

public final Object firstOf(Object e1,
                            Object e2)

Creates parsing expression - "first of". During the execution of this expression parser execute sub-expressions in order until one succeeds. This expressions succeeds if any sub-expression succeeds.

Be aware that in expression firstOf("foo", sequence("foo", "bar")) second sub-expression will never be executed.

Parameters:

e1 - first sub-expression

e2 - second sub-expression

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

firstOf

public final Object firstOf(Object e1,
                            Object e2,
                            Object... rest)

Creates parsing expression - "first of". See firstOf(Object, Object) for more details.

Parameters:

e1 - first sub-expression

e2 - second sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

optional

public final Object optional(Object e)

Creates parsing expression - "optional". During execution of this expression parser will execute sub-expression once. This expression always succeeds, with an empty match if sub-expression fails.

Be aware that this expression is greedy, i.e. expression sequence(optional("foo"), "foo") will never succeed.

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

optional

public final Object optional(Object e1,
                             Object... rest)

Creates parsing expression - "optional". Convenience method equivalent to calling optional(sequence(e, rest)).

Parameters:

e1 - first sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

See Also:

optional(Object), sequence(Object, Object)

oneOrMore

public final Object oneOrMore(Object e)

Creates parsing expression - "one or more". During execution of this expression parser will repeatedly try sub-expression until it fails. This expression succeeds only if sub-expression succeeds at least once.

Be aware that:

• This expression is a greedy, i.e. expression sequence(oneOrMore("foo"), "foo") will never succeed.
• Sub-expression must not allow empty matches, i.e. for expression oneOrMore(optional("foo")) parser will report infinite loop.

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

oneOrMore

public final Object oneOrMore(Object e1,
                              Object... rest)

Creates parsing expression - "one or more". Convenience method equivalent to calling oneOrMore(sequence(e1, rest)).

Parameters:

e1 - first sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

See Also:

oneOrMore(Object), sequence(Object, Object)

zeroOrMore

public final Object zeroOrMore(Object e)

Creates parsing expression - "zero or more". During execution of this expression parser will repeatedly try sub-expression until it fails. This expression always succeeds, with an empty match if sub-expression fails.

Be aware that:

• This expression is greedy, i.e. expression sequence(zeroOrMore("foo"), "foo") will never succeed.
• Sub-expression must not allow empty matches, i.e. for expression zeroOrMore(optional("foo")) parser will report infinite loop.

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

zeroOrMore

public final Object zeroOrMore(Object e1,
                               Object... rest)

Creates parsing expression - "zero or more". Convenience method equivalent to calling zeroOrMore(sequence(e1, rest)).

Parameters:

e1 - sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

See Also:

zeroOrMore(Object), sequence(Object, Object)

next

public final Object next(Object e)

Creates parsing expression - "next". During execution of this expression parser will execute sub-expression once. This expression succeeds only if sub-expression succeeds, but never consumes any input.

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

next

public final Object next(Object e1,
                         Object... rest)

Creates parsing expression - "next". Convenience method equivalent to calling next(sequence(e1, rest)).

Parameters:

e1 - first sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

See Also:

next(Object), sequence(Object, Object)

nextNot

public final Object nextNot(Object e)

Creates parsing expression - "next not". During execution of this expression parser will execute sub-expression once. This expression succeeds only if sub-expression fails.

Parameters:

e - sub-expression

Throws:

IllegalArgumentException - if given argument is not a parsing expression

nextNot

public final Object nextNot(Object e1,
                            Object... rest)

Creates parsing expression - "next not". Convenience method equivalent to calling nextNot(sequence(e1, rest)).

Parameters:

e1 - sub-expression

rest - rest of sub-expressions

Throws:

IllegalArgumentException - if any of given arguments is not a parsing expression

See Also:

nextNot(Object), sequence(Object, Object)

nothing

public final Object nothing()

Creates parsing expression - "nothing". This expression always fails.

convertToExpressions

protected final ParsingExpression[] convertToExpressions(List<Object> expressions)