BL-738

src/main/java/ortus/boxlang/runtime/types/FunctionalBIFAccess.java

@@ -175,4 +175,13 @@ public boolean requiresStrictArguments() {
 		return true;
 	}
 
+	/**
+	 * If we are wrapping a BIF that outputs something, don't block it
+	 * 
+	 * @param context The context in which the function is being invoked
+	 */
+	public boolean canOutput( FunctionBoxContext context ) {
+		return true;
+	}
+
 }

src/main/java/ortus/boxlang/runtime/types/FunctionalMemberAccess.java

@@ -180,4 +180,13 @@ public boolean requiresStrictArguments() {
 		return true;
 	}
 
+	/**
+	 * If we are wrapping a method that outputs something, don't block it
+	 * 
+	 * @param context The context in which the function is being invoked
+	 */
+	public boolean canOutput( FunctionBoxContext context ) {
+		return true;
+	}
+
 }

src/main/java/ortus/boxlang/runtime/types/FunctionalMemberAccessArgs.java

@@ -186,4 +186,13 @@ public boolean requiresStrictArguments() {
 		return true;
 	}
 
+	/**
+	 * If we are wrapping a method that outputs something, don't block it
+	 * 
+	 * @param context The context in which the function is being invoked
+	 */
+	public boolean canOutput( FunctionBoxContext context ) {
+		return true;
+	}
+
 }

src/test/java/TestCases/phase1/CoreLangTest.java

@@ -3755,4 +3755,18 @@ function testMe( string foo ) {
 		assertThat( variables.get( result ) ).isNull();
 	}
 
+
+	@Test
+	public void testPassingBLFunctionsToJavaMethods() {
+		instance.executeSource(
+		    """
+		        	import java.lang.System;
+		        	[1,2,3].stream().forEach( ::echo )
+		    // Lambdas/closures have output=false by default in BL code.
+		        	[1,2,3].stream().forEach( (i) output=true -> echo(i) )
+		      result = getBoxContext().getBuffer().toString();
+		        """, context );
+		assertThat( variables.get( result ) ).isEqualTo( "123123" );
+	}
+
 }