diff --git a/texla/Parser/Blocks/Utilities/MacroParser.py b/texla/Parser/Blocks/Utilities/MacroParser.py
index 5f66daf..d0a853f 100644
--- a/texla/Parser/Blocks/Utilities/MacroParser.py
+++ b/texla/Parser/Blocks/Utilities/MacroParser.py
@@ -1,103 +1,104 @@
 import re
 from . import *
 
 class Macro:
     '''This class represents a Latex macro, a
     newcommands. It saves the definition of the macro
     and it's able to recreate the tex replacement of the macro
     given the params parsed.'''
 
     @staticmethod
     def parse_macro(tex):
         '''
         The function need the options part of the
         \newcommand command, withoud newcommand. It returns the
         parsed Macro object.
         '''
         grammar = [('name','{','}'),
                    ('n_param','[',']'),
                    ('default','[',']'),
                    ('definition','{','}')]
         #now we can parse the options
         things = CommandParser.parse_options(tex, grammar)[0]
         np = things['n_param']
         if np != None:
             things['n_param'] = int(np)
         else:
             things['n_param'] = 0
 
         #now we split the definition around args
         #inserction
-        toks = re.split(r'#(\d+)', things['definition'])
         content = []
-        #we insert into content a list of text tokens and
-        #indexs that are the index of option to be inserted
-        for i in range(len(toks)):
-            if i % 2 == 0:
-                content.append(toks[i])
-            else:
-                content.append(int(toks[i]))
+        if things['definition'] is not None:
+            toks = re.split(r'#(\d+)', things['definition'])
+            #we insert into content a list of text tokens and
+            #indexs that are the index of option to be inserted
+            for i in range(len(toks)):
+                if i % 2 == 0:
+                    content.append(toks[i])
+                else:
+                    content.append(int(toks[i]))
         return Macro(things['name'], things['n_param'],
                     things['default'],content)
 
 
     def __init__(self, name, n_param, default, content):
         self.name = name
         self.n_param = n_param
         self.default = default
         self.content = content
 
 
     def get_tex(self, params, param_default=None):
         '''
         This function return the tex replacement for the
         macro given a list of ordered parameters and,
         if present, the default param (inside [...]).
         '''
         #dictionary for params
         pars = {}
         if self.default != None:
             #if a default param is present
             if param_default != None:
                 #if a default param is found
                 pars[1] = param_default
                 #we had all the params in order
                 if len(params) > 0:
                     for i in range(len(params)):
                         pars[i+2] = params[i]
             else:
                 #we have to check if the
                 #length of param is less then the
                 #required n_param
                 if len(params) < self.n_param:
                     #the default param is the one in
                     #the definition
                     pars[1] = self.default
                     #we had all the params in order
                     if len(params) > 0:
                         for i in range(len(params)):
                             pars[i+2] = params[i]
                 else:
                     #we had all the params in order
                     if len(params) > 0:
                         for i in range(len(params)):
                             pars[i+1] = params[i]
         else:
             #we had all the params in order
             if len(params) > 0:
                 for i in range(len(params)):
                     pars[i+1] = params[i]
         #now we can work with self.content
         tex = []
         for j in range(len(self.content)):
             if j % 2 == 0:
                 tex.append(self.content[j])
             else:
                 #checking if we have the par,
                 #if not, we add a  ''
                 index = self.content[j]
                 if len(pars) >= index:
                     tex.append(pars[index])
                 else:
                     tex.append('')
         return ''.join(tex)