Package org.codehaus.groovy.ast.expr

Class EmptyExpression

java.lang.Object

org.codehaus.groovy.ast.ASTNode

org.codehaus.groovy.ast.AnnotatedNode

org.codehaus.groovy.ast.expr.Expression

org.codehaus.groovy.ast.expr.EmptyExpression

All Implemented Interfaces:

GroovydocHolder<AnnotatedNode>, NodeMetaDataHandler

public class EmptyExpression
extends Expression

Placeholder for an empty expression. Empty expressions are used in closures lists like (;). During class generation empty expressions should be ignored or replaced with a null value.

See Also:

• EmptyStatement

Field Summary

Fields

Modifier and Type	Field	Description
static final EmptyExpression	INSTANCE	Immutable singleton that is recommended for use when source range or any other occurrence-specific metadata is not needed.

Fields inherited from class org.codehaus.groovy.ast.expr.Expression

EMPTY_ARRAY

Fields inherited from interface groovy.lang.groovydoc.GroovydocHolder

DOC_COMMENT

Constructor Summary

Constructors

Constructor	Description
EmptyExpression()

Method Summary

Modifier and Type	Method	Description
Expression	transformExpression(ExpressionTransformer transformer)	Transforms this expression and any nested expressions according to the provided transformer.
void	visit(GroovyCodeVisitor visitor)	Accepts a code visitor for AST traversal and transformation.

Methods inherited from class org.codehaus.groovy.ast.expr.Expression

getType, setType, transformExpressions, transformExpressions

Methods inherited from class org.codehaus.groovy.ast.AnnotatedNode

addAnnotation, addAnnotation, addAnnotations, getAnnotations, getAnnotations, getDeclaringClass, getGroovydoc, getInstance, hasNoRealSourcePosition, isSynthetic, setDeclaringClass, setHasNoRealSourcePosition, setSynthetic

Methods inherited from class org.codehaus.groovy.ast.ASTNode

copyNodeMetaData, getColumnNumber, getLastColumnNumber, getLastLineNumber, getLineNumber, getMetaDataMap, getText, setColumnNumber, setLastColumnNumber, setLastLineNumber, setLineNumber, setMetaDataMap, setSourcePosition

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.codehaus.groovy.ast.NodeMetaDataHandler

copyNodeMetaData, getNodeMetaData, getNodeMetaData, getNodeMetaData, newMetaDataMap, putNodeMetaData, removeNodeMetaData, setNodeMetaData

Field Details

INSTANCE

public static final EmptyExpression INSTANCE

Immutable singleton that is recommended for use when source range or any other occurrence-specific metadata is not needed.

Constructor Details

EmptyExpression

public EmptyExpression()

See Also:

• INSTANCE

Method Details

transformExpression

public Expression transformExpression(ExpressionTransformer transformer)

Description copied from class: Expression

Transforms this expression and any nested expressions according to the provided transformer. This method is called during AST transformation phases and must recursively transform any nested expressions to support full AST tree transformation.

Specified by:

transformExpression in class Expression

Parameters:

transformer - the ExpressionTransformer to apply

Returns:

a transformed copy of this expression (or this expression itself if no changes are needed)

visit

public void visit(GroovyCodeVisitor visitor)

Description copied from class: ASTNode

Accepts a code visitor for AST traversal and transformation. Subclasses must implement this method to support visitor pattern-based processing. The visitor pattern enables decoupling of AST structure from processing logic.

Overrides:

visit in class ASTNode

Parameters:

visitor - the GroovyCodeVisitor to process this node