diff --git a/ate/testcase.py b/ate/testcase.py
index d192e45b..33a93967 100644
--- a/ate/testcase.py
+++ b/ate/testcase.py
@@ -5,8 +5,8 @@ import re
 from ate import exception, utils
 
 variable_regexp = r"\$([\w_]+)"
-function_regexp = r"\$\{[\w_]+\([\$\w_ =,]*\)\}"
-function_regexp_compile = re.compile(r"^\$\{([\w_]+)\(([\$\w_ =,]*)\)\}$")
+function_regexp = r"\$\{([\w_]+\([\$\w_ =,]*\))\}"
+function_regexp_compile = re.compile(r"^([\w_]+)\(([\$\w_ =,]*)\)$")
 
 
 def extract_variables(content):
@@ -29,11 +29,11 @@ def extract_functions(content):
     @param (str) content
     @return (list) functions list
 
-    e.g. ${func(5)} => ["${func(5)}"]
-         ${func(a=1, b=2)} => ["${func(a=1, b=2)}"]
+    e.g. ${func(5)} => ["func(5)"]
+         ${func(a=1, b=2)} => ["func(a=1, b=2)"]
          /api/1000?_t=${get_timestamp()} => ["get_timestamp()"]
          /api/${add(1, 2)} => ["add(1, 2)"]
-         "/api/${add(1, 2)}?_t=${get_timestamp()}" => ["${add(1, 2)}", "${get_timestamp()}"]
+         "/api/${add(1, 2)}?_t=${get_timestamp()}" => ["add(1, 2)", "get_timestamp()"]
     """
     try:
         return re.findall(function_regexp, content)
@@ -60,11 +60,11 @@ def parse_function(content):
     @param (str) content
     @return (dict) function name and args
 
-    e.g. ${func()} => {'func_name': 'func', 'args': [], 'kwargs': {}}
-         ${func(5)} => {'func_name': 'func', 'args': [5], 'kwargs': {}}
-         ${func(1, 2)} => {'func_name': 'func', 'args': [1, 2], 'kwargs': {}}
-         ${func(a=1, b=2)} => {'func_name': 'func', 'args': [], 'kwargs': {'a': 1, 'b': 2}}
-         ${func(1, 2, a=3, b=4)} => {'func_name': 'func', 'args': [1, 2], 'kwargs': {'a':3, 'b':4}}
+    e.g. func() => {'func_name': 'func', 'args': [], 'kwargs': {}}
+         func(5) => {'func_name': 'func', 'args': [5], 'kwargs': {}}
+         func(1, 2) => {'func_name': 'func', 'args': [1, 2], 'kwargs': {}}
+         func(a=1, b=2) => {'func_name': 'func', 'args': [], 'kwargs': {'a': 1, 'b': 2}}
+         func(1, 2, a=3, b=4) => {'func_name': 'func', 'args': [1, 2], 'kwargs': {'a':3, 'b':4}}
     """
     function_meta = {
         "args": [],
@@ -147,6 +147,7 @@ class TestcaseParser(object):
             kwargs = self.parse_content_with_bindings(kwargs)
             eval_value = func(*args, **kwargs)
 
+            func_content = "${" + func_content + "}"
             if func_content == content:
                 # content is a variable
                 content = eval_value
diff --git a/tests/test_testcase.py b/tests/test_testcase.py
index 9cdee695..1f6af65b 100644
--- a/tests/test_testcase.py
+++ b/tests/test_testcase.py
@@ -131,27 +131,27 @@ class TestcaseParserUnittest(unittest.TestCase):
 
     def test_parse_function(self):
         self.assertEqual(
-            testcase.parse_function("${func()}"),
+            testcase.parse_function("func()"),
             {'func_name': 'func', 'args': [], 'kwargs': {}}
         )
         self.assertEqual(
-            testcase.parse_function("${func(5)}"),
+            testcase.parse_function("func(5)"),
             {'func_name': 'func', 'args': [5], 'kwargs': {}}
         )
         self.assertEqual(
-            testcase.parse_function("${func(1, 2)}"),
+            testcase.parse_function("func(1, 2)"),
             {'func_name': 'func', 'args': [1, 2], 'kwargs': {}}
         )
         self.assertEqual(
-            testcase.parse_function("${func(a=1, b=2)}"),
+            testcase.parse_function("func(a=1, b=2)"),
             {'func_name': 'func', 'args': [], 'kwargs': {'a': 1, 'b': 2}}
         )
         self.assertEqual(
-            testcase.parse_function("${func(a= 1, b =2)}"),
+            testcase.parse_function("func(a= 1, b =2)"),
             {'func_name': 'func', 'args': [], 'kwargs': {'a': 1, 'b': 2}}
         )
         self.assertEqual(
-            testcase.parse_function("${func(1, 2, a=3, b=4)}"),
+            testcase.parse_function("func(1, 2, a=3, b=4)"),
             {'func_name': 'func', 'args': [1, 2], 'kwargs': {'a': 3, 'b': 4}}
         )
 
@@ -232,35 +232,35 @@ class TestcaseParserUnittest(unittest.TestCase):
     def test_extract_functions(self):
         self.assertEqual(
             testcase.extract_functions("${func()}"),
-            ["${func()}"]
+            ["func()"]
         )
         self.assertEqual(
             testcase.extract_functions("${func(5)}"),
-            ["${func(5)}"]
+            ["func(5)"]
         )
         self.assertEqual(
             testcase.extract_functions("${func(a=1, b=2)}"),
-            ["${func(a=1, b=2)}"]
+            ["func(a=1, b=2)"]
         )
         self.assertEqual(
             testcase.extract_functions("${func(1, $b, c=$x, d=4)}"),
-            ["${func(1, $b, c=$x, d=4)}"]
+            ["func(1, $b, c=$x, d=4)"]
         )
         self.assertEqual(
             testcase.extract_functions("/api/1000?_t=${get_timestamp()}"),
-            ["${get_timestamp()}"]
+            ["get_timestamp()"]
         )
         self.assertEqual(
             testcase.extract_functions("/api/${add(1, 2)}"),
-            ["${add(1, 2)}"]
+            ["add(1, 2)"]
         )
         self.assertEqual(
             testcase.extract_functions("/api/${add(1, 2)}?_t=${get_timestamp()}"),
-            ["${add(1, 2)}", "${get_timestamp()}"]
+            ["add(1, 2)", "get_timestamp()"]
         )
         self.assertEqual(
             testcase.extract_functions("abc${func(1, 2, a=3, b=4)}def"),
-            ["${func(1, 2, a=3, b=4)}"]
+            ["func(1, 2, a=3, b=4)"]
         )
 
     def test_eval_content_functions(self):