Use loop() to recurse instead of loop.recurse()

CHANGELOG

@@ -1,6 +1,6 @@
 # 4.0.0 (2024-XX-XX)
 
- * Add support for recursive loops (via `loop.recurse()`)
+ * Add support for recursive loops (via the `loop()` function)
  * Add `loop.changed`, `loop.previous`, `loop.next`, and `loop.cycle` variables
  * Make `loop.last` always available (even for non-countable iterators)
  * Change the compilation of `for` loops to throw an exception when a `loop.*` variable is not defined

src/ExpressionParser.php

@@ -460,6 +460,15 @@ class ExpressionParser
                 }
 
                 return new GetAttrExpression($args->getNode('0'), $args->getNode('1'), \count($args) > 2 ? $args->getNode('2') : null, Template::ANY_CALL, $line);
+            case 'loop':
+                $args = $this->parseArguments();
+                if (\count($args) < 1) {
+                    throw new SyntaxError('The "loop" function takes an iterator as an argument.', $line, $this->parser->getStream()->getSourceContext());
+                }
+                $recurseArgs = new ArrayExpression([], $line);
+                $recurseArgs->addElement($args->getNode('0'));
+
+                return new GetAttrExpression(new NameExpression('loop', $line), new ConstantExpression('__invoke', $line), $recurseArgs, Template::METHOD_CALL, $line);
             default:
                 if (null !== $alias = $this->parser->getImportedSymbol('function', $name)) {
                     $arguments = new ArrayExpression([], $line);

src/NodeVisitor/ForNodeVisitor.php

@@ -43,14 +43,14 @@ final class ForNodeVisitor implements NodeVisitorInterface
             return $node;
         }
 
-        // We look for exactly {{ loop.recurse(...) }}
+        // We look for exactly {{ loop.__invoke(...) }}
         $exprNode = $node->getNode('expr');
         if (
             $exprNode instanceof GetAttrExpression
             && $exprNode->getNode('node') instanceof NameExpression
             && 'loop' === $exprNode->getNode('node')->getAttribute('name')
             && $exprNode->getNode('attribute') instanceof ConstantExpression
-            && 'recurse' === $exprNode->getNode('attribute')->getAttribute('value')
+            && '__invoke' === $exprNode->getNode('attribute')->getAttribute('value')
         ) {
             $exprNode->setAttribute('is_generator', true);
         }

src/Runtime/LoopContext.php

@@ -103,7 +103,7 @@ final class LoopContext
         return $values[$this->getIndex0() % count($values)];
     }
 
-    public function recurse($iterator): \Generator
+    public function __invoke($iterator): \Generator
     {
         yield from ($this->recurseFunc)(new LoopIterator($iterator), $this->parent, $this->blocks, $this->recurseFunc, $this->depth + 1);
     }