com.oracle.truffle.regex.tregex.parser.ast

Class PositionAssertion

java.lang.Object

com.oracle.truffle.regex.tregex.parser.ast.RegexASTNode

com.oracle.truffle.regex.tregex.parser.ast.Term

com.oracle.truffle.regex.tregex.parser.ast.PositionAssertion

All Implemented Interfaces:

AbstractState<Term,ASTTransition>, JsonConvertible

public class PositionAssertion
extends Term

An assertion that succeeds when encountered at the beginning or at the end of the string we are searching in.

Corresponds to the ^ and $ right-hand sides of the Assertion goal symbol in the ECMAScript RegExp syntax.

PositionAssertion nodes are also used for state sets of NFA initial states, which is why they can have a next-pointer (PositionAssertion.getNext()), see RegexAST.getNFAAnchoredInitialState(int).

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PositionAssertion.Type The position assertions supported by ECMAScript RegExps.

Field Summary

Fields

Modifier and Type	Field and Description
PositionAssertion.Type	type Indicates which position assertion this node represents.

Method Summary

Modifier and Type	Method and Description
PositionAssertion	copy(RegexAST ast) Copy this node only, without any child nodes.
Term	copyRecursive(RegexAST ast, CompilationBuffer compilationBuffer) Recursively copy this subtree.
boolean	equalsSemantic(RegexASTNode obj)
RegexASTNode	getNext() Points to the body of a regular expression when this node is treated as an initial state of an NFA.
boolean	isCaret()
boolean	isDollar()
void	setNext(RegexASTNode next)
JsonValue	toJson()
String	toString()

Methods inherited from class com.oracle.truffle.regex.tregex.parser.ast.Term

getSeqIndex, getSubTreeParent, setSeqIndex

Methods inherited from class com.oracle.truffle.regex.tregex.parser.ast.RegexASTNode

asAtomicGroup, asBackReference, asCharacterClass, asConditionalBackReferenceGroup, asGroup, asLookAheadAssertion, asLookAroundAssertion, asLookBehindAssertion, asMatchFound, asPositionAssertion, asQuantifiableTerm, asSequence, asSubtreeRootNode, astNodeId, endsWithDollar, getFlags, getId, getMaxPath, getMinPath, getParent, getPrefixLengthMax, getPrefixLengthMin, hasBackReferences, hasCaptureGroups, hasCaret, hasDollar, hasEmptyGuard, hasLookAheads, hasLookBehinds, hasLoops, hasQuantifiers, hasVariablePrefixLength, idInitialized, incMaxPath, incMaxPath, incMinPath, incMinPath, isAtomicGroup, isBackReference, isCharacterClass, isConditionalBackReferenceGroup, isDead, isExpandedQuantifier, isFlagSet, isGroup, isInLookAheadAssertion, isInLookBehindAssertion, isLookAheadAssertion, isLookAroundAssertion, isLookBehindAssertion, isMatchFound, isPositionAssertion, isPrefix, isQuantifiableTerm, isRoot, isSequence, isSubtreeRoot, markAsDead, setDead, setEmptyGuard, setEndsWithDollar, setEndsWithDollar, setExpandedQuantifier, setFlag, setFlag, setFlags, setHasBackReferences, setHasCaptureGroups, setHasCaret, setHasCaret, setHasDollar, setHasDollar, setHasLookAheads, setHasLookBehinds, setHasLoops, setHasLoops, setHasQuantifiers, setId, setMaxPath, setMinPath, setParent, setPrefix, setPrefixLengthMax, setPrefixLengthMin, setStartsWithCaret, setStartsWithCaret, startsWithCaret, toJson, toStringWithID

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.oracle.truffle.regex.tregex.automaton.AbstractState

getId

Field Detail

type

public final PositionAssertion.Type type

Indicates which position assertion this node represents.

Method Detail

copy

public PositionAssertion copy(RegexAST ast)

Description copied from class: RegexASTNode

Copy this node only, without any child nodes. The ID and minPath of the copied nodes is left unset.

Specified by:

copy in class Term

Parameters:

ast - RegexAST the node should belong to.

Returns:

A shallow copy of this node.

copyRecursive

public Term copyRecursive(RegexAST ast,
                          CompilationBuffer compilationBuffer)

Description copied from class: RegexASTNode

Recursively copy this subtree. This method should be used instead of CopyVisitor if the copying process is required to be thread-safe. The ID and minPath of the copied nodes is left unset.

Specified by:

copyRecursive in class Term

Parameters:

ast - RegexAST the new nodes should belong to.

Returns:

A deep copy of this node.

getNext

public RegexASTNode getNext()

Points to the body of a regular expression when this node is treated as an initial state of an NFA. If this PositionAssertion.isCaret(), then this returns the next expression. If this PositionAssertion.isDollar(), then this returns the previous expression.

setNext

public void setNext(RegexASTNode next)

isCaret

public boolean isCaret()

Overrides:

isCaret in class RegexASTNode

isDollar

public boolean isDollar()

Overrides:

isDollar in class RegexASTNode

equalsSemantic

public boolean equalsSemantic(RegexASTNode obj)

Specified by:

equalsSemantic in class RegexASTNode

toString

public String toString()

Overrides:

toString in class Object

toJson

public JsonValue toJson()