com.oracle.truffle.regex.tregex.parser

Class RegexASTBuilder

java.lang.Object

com.oracle.truffle.regex.tregex.parser.RegexASTBuilder

public final class RegexASTBuilder
extends Object

This class is used to generate regex ASTs. The provided methods append nodes to the AST.

Constructor Summary

Constructors

Constructor and Description
RegexASTBuilder(RegexLanguage language, RegexSource source, RegexFlags flags, CompilationBuffer compilationBuffer)

Method Summary

Modifier and Type	Method and Description
void	addBackReference(int groupNumber)
void	addBackReference(Token.BackReference token) Adds a new BackReference to the current Sequence.
void	addCaret()
void	addCharClass(CodePointSet charSet)
void	addCharClass(CodePointSet charSet, boolean wasSingleChar)
void	addCharClass(Token.CharacterClass token) Adds a new CharacterClass to the current Sequence.
void	addCopy(Token token, Group sourceGroup) Adds a copy of sourceGroup to the current Sequence.
void	addDeadNode() Adds a dead node (an empty character class) to the current Sequence.
void	addDollar()
void	addPositionAssertion(Token token) Adds a new PositionAssertion to the current Sequence.
void	addQuantifier(Token.Quantifier quantifier) Adds a quantifier to the current Term.
void	addSubexpressionCall(int groupNumber)
boolean	curGroupIsRoot() Indicates whether the builder is currently in the root group or in some nested group.
Group	getCurGroup() Returns the current Group.
Sequence	getCurSequence() Returns the current Sequence into which new Terms will be added.
Term	getCurTerm() Returns the last Term inserted into the current Sequence.
void	nextSequence() Adds a new Sequence to the current Group.
void	popGroup()
void	popGroup(Token token) Close and leave the current group.
RegexAST	popRootGroup() This is the build method of this Builder.
void	pushAtomicGroup()
void	pushAtomicGroup(Token token)
void	pushCaptureGroup()
void	pushCaptureGroup(Token token) Creates and enters a new capture group.
void	pushGroup()
void	pushGroup(Token token) Creates and enters a new non-capturing group.
void	pushLookAheadAssertion(boolean negate)
void	pushLookAheadAssertion(Token token, boolean negate) Creates and enters a new look-ahead assertion.
void	pushLookBehindAssertion(boolean negate)
void	pushLookBehindAssertion(Token token, boolean negate) Creates and enters a new look-behind assertion.
void	pushRootGroup() This should be called first after creating a new RegexASTBuilder.
void	pushRootGroup(boolean rootCapture) Like RegexASTBuilder.pushRootGroup(), but allows creating a non-capturing root group.
void	removeCurTerm() Removes the current Term from the current Sequence.
void	replaceCurTermWithDeadNode() Replaces the current Term with a dead node.
void	wrapCurTermInAtomicGroup() Wraps the current Term in an atomic group.
void	wrapCurTermInGroup() Wraps the current Term in a non-capturing group.

Methods inherited from class java.lang.Object

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

Constructor Detail

RegexASTBuilder

public RegexASTBuilder(RegexLanguage language,
                       RegexSource source,
                       RegexFlags flags,
                       CompilationBuffer compilationBuffer)

Method Detail

getCurGroup

public Group getCurGroup()

Returns the current Group. Any new Terms will be added to its last Sequence (the one returned by RegexASTBuilder.curSequence).

getCurSequence

public Sequence getCurSequence()

Returns the current Sequence into which new Terms will be added.

getCurTerm

public Term getCurTerm()

Returns the last Term inserted into the current Sequence. This will be null if a new Sequence or Group was just started.

curGroupIsRoot

public boolean curGroupIsRoot()

Indicates whether the builder is currently in the root group or in some nested group.

Returns:

true if the builder is in the root group

pushRootGroup

public void pushRootGroup()

This should be called first after creating a new RegexASTBuilder. This will create and enter the root capture group (group number 0).

pushRootGroup

public void pushRootGroup(boolean rootCapture)

Like RegexASTBuilder.pushRootGroup(), but allows creating a non-capturing root group. This is useful for building intermediate ASTs that are then pasted into other ASTs.

popRootGroup

public RegexAST popRootGroup()

This is the build method of this Builder. As such, it should be the last method you call on an RegexASTBuilder instance.

Returns:

the generated AST

pushGroup

public void pushGroup(Token token)

Creates and enters a new non-capturing group. This call should be paired with a call to RegexASTBuilder.popGroup(com.oracle.truffle.regex.tregex.parser.Token).

Parameters:

token - a Token whose source section should be included in the group's source sections, or null if none

pushGroup

public void pushGroup()

pushCaptureGroup

public void pushCaptureGroup(Token token)

Creates and enters a new capture group. This call should be paired with a call to RegexASTBuilder.popGroup(com.oracle.truffle.regex.tregex.parser.Token).

Parameters:

token - a Token whose source section should be included in the group's source sections, or null if none

pushCaptureGroup

public void pushCaptureGroup()

pushLookAheadAssertion

public void pushLookAheadAssertion(Token token,
                                   boolean negate)

Creates and enters a new look-ahead assertion. This call should be paired with a call to RegexASTBuilder.popGroup(com.oracle.truffle.regex.tregex.parser.Token).

Parameters:

token - a Token whose source section should be included in the assertion's source sections, or null if none

negate - true if the look-ahead assertion is to be negative

pushLookAheadAssertion

public void pushLookAheadAssertion(boolean negate)

pushLookBehindAssertion

public void pushLookBehindAssertion(Token token,
                                    boolean negate)

Creates and enters a new look-behind assertion. This call should be paired with a call to RegexASTBuilder.popGroup(com.oracle.truffle.regex.tregex.parser.Token).

Parameters:

token - a Token whose source section should be included in the assertion's source sections, or null if none

negate - true if the look-behind assertion is to be negative

pushLookBehindAssertion

public void pushLookBehindAssertion(boolean negate)

pushAtomicGroup

public void pushAtomicGroup(Token token)

pushAtomicGroup

public void pushAtomicGroup()

popGroup

public void popGroup(Token token)

Close and leave the current group. This should be paired either with RegexASTBuilder.pushGroup(Token), RegexASTBuilder.pushCaptureGroup(Token), RegexASTBuilder.pushLookAheadAssertion(Token, boolean) or RegexASTBuilder.pushLookBehindAssertion(Token, boolean).

Parameters:

token - a Token whose source section should be included in the group's or assertion's source sections, or null if none

popGroup

public void popGroup()

nextSequence

public void nextSequence()

Adds a new Sequence to the current Group. In a parser, you would call this method after encountering the vertical bar operator.

addCharClass

public void addCharClass(Token.CharacterClass token)

Adds a new CharacterClass to the current Sequence.

Parameters:

token - aside from the source sections, the token most importantly contains the set of code points to be included in the character class and a flag indicating whether it corresponds to a single character in the regex (i.e. a literal or an escaped character)

addCharClass

public void addCharClass(CodePointSet charSet,
                         boolean wasSingleChar)

addCharClass

public void addCharClass(CodePointSet charSet)

addBackReference

public void addBackReference(Token.BackReference token)

Adds a new BackReference to the current Sequence.

Parameters:

token - aside from the source sections, this contains the number of the group being referenced

addBackReference

public void addBackReference(int groupNumber)

addSubexpressionCall

public void addSubexpressionCall(int groupNumber)

addPositionAssertion

public void addPositionAssertion(Token token)

Adds a new PositionAssertion to the current Sequence.

Parameters:

token - aside from the source sections, the kind of this token indicates whether this is the ^ assertion or the $ assertion

addCaret

public void addCaret()

addDollar

public void addDollar()

addQuantifier

public void addQuantifier(Token.Quantifier quantifier)

Adds a quantifier to the current Term.

Parameters:

quantifier - this token contains a specification of the quantifier's semantics, along with the source section data

addCopy

public void addCopy(Token token,
                    Group sourceGroup)

Adds a copy of sourceGroup to the current Sequence.

Parameters:

token - a token indicating which source sections should be attributed to the copied group

sourceGroup - the Group to be copied

removeCurTerm

public void removeCurTerm()

Removes the current Term from the current Sequence.

addDeadNode

public void addDeadNode()

Adds a dead node (an empty character class) to the current Sequence.

replaceCurTermWithDeadNode

public void replaceCurTermWithDeadNode()

Replaces the current Term with a dead node.

wrapCurTermInGroup

public void wrapCurTermInGroup()

Wraps the current Term in a non-capturing group.

wrapCurTermInAtomicGroup

public void wrapCurTermInAtomicGroup()

Wraps the current Term in an atomic group. This can be useful when implementing possessive quantifiers.