Avoid using len(x) to check if x is empty

Author: iMichka

pygccxml/declarations/enumeration.py

@@ -101,7 +101,7 @@ def append_value(self, valuename, valuenum=None):
         """
         # No number given? Then use the previous one + 1
         if valuenum is None:
-            if len(self._values) == 0:
+            if not self._values:
                 valuenum = 0
             else:
                 valuenum = self._values[-1][1] + 1

pygccxml/declarations/matcher.py

@@ -102,7 +102,7 @@ def get_single(decl_matcher, decls, recursive=True):
         answer = matcher.find(decl_matcher, decls, recursive)
         if len(answer) == 1:
             return answer[0]
-        elif len(answer) == 0:
+        elif not answer:
             raise matcher.declaration_not_found_t(decl_matcher)
         else:
             raise matcher.multiple_declarations_found_t(decl_matcher)

pygccxml/parser/directory_cache.py

@@ -515,7 +515,7 @@ def update_id_counter(self):
         """Update the `id_` counter so that it doesn't grow forever.
         """
 
-        if len(self.__entries) == 0:
+        if not self.__entries:
             self.__next_id = 1
         else:
             self.__next_id = max(self.__entries.keys()) + 1

pygccxml/parser/source_reader.py

@@ -227,11 +227,12 @@ def __add_symbols(self, cmd):
 
         """
 
-        if len(self.__config.define_symbols) != 0:
+        if self.__config.define_symbols:
             symbols = self.__config.define_symbols
             cmd.append(''.join(
                 [' -D"%s"' % defined_symbol for defined_symbol in symbols]))
-        if len(self.__config.undefine_symbols) != 0:
+
+        if self.__config.undefine_symbols:
             un_symbols = self.__config.undefine_symbols
             cmd.append(
                 ''.join([' -U"%s"' % undefined_symbol for