diff --git a/src/ControlStructure/FunctionToken.php b/src/ControlStructure/FunctionToken.php
index 523ace4..61ea545 100644
--- a/src/ControlStructure/FunctionToken.php
+++ b/src/ControlStructure/FunctionToken.php
@@ -33,7 +33,9 @@ class FunctionToken implements ControlStructure {
 
     protected function printFunction($context, ?string $arguments) : string
     {
-        return "<?php function $arguments { ?>";
+        $name = trim(explode('(', $arguments, 2)[0]);
+
+        return "<?php if (! function_exists(__NAMESPACE__ . '\\$name')) { function $arguments { ?>";
     }
 
     protected function printReturn($context, ?string $arguments) : string
@@ -43,6 +45,6 @@ class FunctionToken implements ControlStructure {
 
     protected function printEndFunction($context) : string
     {
-        return "<?php } ?>";
+        return "<?php } } ?>";
     }
 }
\ No newline at end of file