Package org.codehaus.groovy.classgen

Class VariableScopeVisitor.InstanceofFlowBindings

java.lang.Object

org.codehaus.groovy.classgen.VariableScopeVisitor.InstanceofFlowBindings

Enclosing class:

VariableScopeVisitor

public static final class VariableScopeVisitor.InstanceofFlowBindings
extends Object

Flow-sensitive result for JEP 394 instanceof pattern bindings (GROOVY-12242) — the Groovy equivalent of the JLS §6.3.1 “introduced by” sets.

One type, two views of the same analysis:

• whenTrue()/whenFalse() — pattern VariableExpressions for VariableScopeVisitor to declare into lexical scopes;
• whenTrueNames()/whenFalseNames() — the same sets as names for classgen to path-hide CompileStack slots.

VariableScopeVisitor runs the analysis once via of(org.codehaus.groovy.ast.expr.Expression), declares from the variable lists, and attaches this instance as AST metadata (put(org.codehaus.groovy.ast.ASTNode, org.codehaus.groovy.classgen.VariableScopeVisitor.InstanceofFlowBindings)/get(org.codehaus.groovy.ast.ASTNode)). Later phases must use get(org.codehaus.groovy.ast.ASTNode) only — never re-call of(org.codehaus.groovy.ast.expr.Expression) on the condition.

Covered shapes: e instanceof T t, e !instanceof T t (native form and !(e instanceof T t)), !expr, a && b, a || b. All other shapes yield EMPTY (conservative: no definite bindings).

Since:

6.0.0

See Also:

• VariableScopeVisitor

Field Summary

Fields

Modifier and Type	Field	Description
static final VariableScopeVisitor.InstanceofFlowBindings	EMPTY	Singleton for "no pattern variables on either path".
static final Object	KEY	Metadata key for NodeMetaDataHandler.putNodeMetaData(java.lang.Object, java.lang.Object)/getNodeMetaData.

Method Summary

Modifier and Type	Method	Description
Set<String>	allNames()	All pattern-variable names in either path (stable encounter order).
static Set<String>	allPatternNames(Expression expression)	Names of all pattern variables in expression, regardless of definite-assignment path.
static boolean	containsPattern(Expression expression)	Returns true if expression contains any JEP 394 type-pattern node at any depth.
static VariableScopeVisitor.InstanceofFlowBindings	get(ASTNode node)	Returns the analysis result previously attached to node, or EMPTY if none (no path-live pattern variables).
boolean	isEmpty()	Whether any pattern variable is bound on either path.
static VariableScopeVisitor.InstanceofFlowBindings	of(Expression expression)	Analyses expression for definite instanceof pattern bindings.
static void	put(ASTNode node, VariableScopeVisitor.InstanceofFlowBindings bindings)	Attaches this analysis result to node for later phases.
List<VariableExpression>	whenFalse()	Pattern variables definitely assigned when the condition is false.
Set<String>	whenFalseNames()	Names of pattern variables bound when the condition is false.
List<VariableExpression>	whenTrue()	Pattern variables definitely assigned when the condition is true.
Set<String>	whenTrueNames()	Names of pattern variables bound when the condition is true.

Methods inherited from class java.lang.Object

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

Field Details

KEY

public static final Object KEY

Metadata key for NodeMetaDataHandler.putNodeMetaData(java.lang.Object, java.lang.Object)/getNodeMetaData.

EMPTY

public static final VariableScopeVisitor.InstanceofFlowBindings EMPTY

Singleton for "no pattern variables on either path".

Method Details

whenTrue

public List<VariableExpression> whenTrue()

Pattern variables definitely assigned when the condition is true. Used by VariableScopeVisitor to declare into scopes.

whenFalse

public List<VariableExpression> whenFalse()

Pattern variables definitely assigned when the condition is false. Used by VariableScopeVisitor to declare into scopes.

whenTrueNames

public Set<String> whenTrueNames()

Names of pattern variables bound when the condition is true. Used by classgen for CompileStack path-hide; same set as whenTrue().

whenFalseNames

public Set<String> whenFalseNames()

Names of pattern variables bound when the condition is false. Used by classgen for CompileStack path-hide; same set as whenFalse().

isEmpty

public boolean isEmpty()

Whether any pattern variable is bound on either path.

allNames

public Set<String> allNames()

All pattern-variable names in either path (stable encounter order).

put

public static void put(ASTNode node,
 VariableScopeVisitor.InstanceofFlowBindings bindings)

Attaches this analysis result to node for later phases. No-op when bindings is null or EMPTY.

get

public static VariableScopeVisitor.InstanceofFlowBindings get(ASTNode node)

Returns the analysis result previously attached to node, or EMPTY if none (no path-live pattern variables).

of

public static VariableScopeVisitor.InstanceofFlowBindings of(Expression expression)

Analyses expression for definite instanceof pattern bindings. Call only from VariableScopeVisitor (or tests); classgen must use get(ASTNode).

Parameters:

expression - a boolean condition (may be a BooleanExpression wrapper); null yields EMPTY

Returns:

the true/false binding sets; never null

containsPattern

public static boolean containsPattern(Expression expression)

Returns true if expression contains any JEP 394 type-pattern node at any depth. Full subtree walk (unlike of(org.codehaus.groovy.ast.expr.Expression)). Used by tests and diagnostics; classgen has its own structural check for expression-statement isolation.

allPatternNames

public static Set<String> allPatternNames(Expression expression)

Names of all pattern variables in expression, regardless of definite-assignment path. Full tree walk; for tests/diagnostics. Classgen tracks allocated slots via CompileStack instead.