diff --git a/src/FunctionLike.php b/src/FunctionLike.php
new file mode 100644
index 00000000..73580bf0
--- /dev/null
+++ b/src/FunctionLike.php
@@ -0,0 +1,13 @@
+<?php
+/*---------------------------------------------------------------------------------------------
+ * Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+namespace Microsoft\PhpParser;
+
+/**
+ * Interface for recognizing functions easily.
+ * Each Node that implements this interface can be considered a function.
+ */
+interface FunctionLike {}
\ No newline at end of file
diff --git a/src/Node/Expression/AnonymousFunctionCreationExpression.php b/src/Node/Expression/AnonymousFunctionCreationExpression.php
index 5f39b3df..08a16635 100644
--- a/src/Node/Expression/AnonymousFunctionCreationExpression.php
+++ b/src/Node/Expression/AnonymousFunctionCreationExpression.php
@@ -6,6 +6,7 @@
 
 namespace Microsoft\PhpParser\Node\Expression;
 
+use Microsoft\PhpParser\FunctionLike;
 use Microsoft\PhpParser\Node\Expression;
 use Microsoft\PhpParser\Node\FunctionBody;
 use Microsoft\PhpParser\Node\FunctionHeader;
@@ -13,7 +14,7 @@
 use Microsoft\PhpParser\Node\FunctionUseClause;
 use Microsoft\PhpParser\Token;
 
-class AnonymousFunctionCreationExpression extends Expression {
+class AnonymousFunctionCreationExpression extends Expression implements FunctionLike {
     /** @var Token | null */
     public $staticModifier;
 
diff --git a/src/Node/MethodDeclaration.php b/src/Node/MethodDeclaration.php
index ae90ad38..4d596632 100644
--- a/src/Node/MethodDeclaration.php
+++ b/src/Node/MethodDeclaration.php
@@ -6,11 +6,12 @@
 
 namespace Microsoft\PhpParser\Node;
 
+use Microsoft\PhpParser\FunctionLike;
 use Microsoft\PhpParser\Node;
 use Microsoft\PhpParser\Token;
 use Microsoft\PhpParser\TokenKind;
 
-class MethodDeclaration extends Node {
+class MethodDeclaration extends Node implements FunctionLike {
     /** @var Token[] */
     public $modifiers;
 
diff --git a/src/Node/Statement/FunctionDeclaration.php b/src/Node/Statement/FunctionDeclaration.php
index a0877eca..f186305e 100644
--- a/src/Node/Statement/FunctionDeclaration.php
+++ b/src/Node/Statement/FunctionDeclaration.php
@@ -6,6 +6,7 @@
 
 namespace Microsoft\PhpParser\Node\Statement;
 
+use Microsoft\PhpParser\FunctionLike;
 use Microsoft\PhpParser\NamespacedNameInterface;
 use Microsoft\PhpParser\NamespacedNameTrait;
 use Microsoft\PhpParser\Node\FunctionBody;
@@ -13,7 +14,7 @@
 use Microsoft\PhpParser\Node\FunctionReturnType;
 use Microsoft\PhpParser\Node\StatementNode;
 
-class FunctionDeclaration extends StatementNode implements NamespacedNameInterface {
+class FunctionDeclaration extends StatementNode implements NamespacedNameInterface, FunctionLike {
     use FunctionHeader, FunctionReturnType, FunctionBody;
     use NamespacedNameTrait;