Clean up cdecl.py a bit
diff --git a/examples/cdecl.py b/examples/cdecl.py
index 92ac715..a510087 100644
--- a/examples/cdecl.py
+++ b/examples/cdecl.py
@@ -6,9 +6,8 @@
#
# The AST generated by pycparser from the given declaration is traversed
# recursively to build the explanation. Note that the declaration must be a
-# valid external declaration in C. All the types used in it must be defined with
-# typedef, or parsing will fail. The definition can be arbitrary - pycparser
-# doesn't really care what the type is defined to be, only that it's a type.
+# valid external declaration in C. As shown below, typedef can be optionally
+# expanded.
#
# For example:
#
@@ -17,7 +16,7 @@
# explain_c_declaration(c_decl)
# => ar is a pointer to array[10] of pointer to const Node
#
-# struct and typedef are expanded when according arguments are set:
+# struct and typedef can be optionally expanded:
#
# explain_c_declaration(c_decl, expand_typedef=True)
# => ar is a pointer to array[10] of pointer to const int
@@ -48,8 +47,11 @@
""" Parses the declaration in c_decl and returns a text
explanation as a string.
- The last external node of the string is used, to allow
- earlier typedefs for used types.
+ The last external node of the string is used, to allow earlier typedefs
+ for used types.
+
+ expand_struct=True will spell out struct definitions recursively.
+ expand_typedef=True will expand typedef'd types.
"""
parser = c_parser.CParser()
@@ -125,32 +127,35 @@
('containing {%s}' % members if members else ''))
-def expand_struct_typedef(cdecl, file_ast, expand_struct=False, expand_typedef=False):
- """Expand struct & typedef in context of file_ast and return a new expanded node"""
+def expand_struct_typedef(cdecl, file_ast,
+ expand_struct=False,
+ expand_typedef=False):
+ """Expand struct & typedef and return a new expanded node."""
decl_copy = copy.deepcopy(cdecl)
_expand_in_place(decl_copy, file_ast, expand_struct, expand_typedef)
return decl_copy
def _expand_in_place(decl, file_ast, expand_struct=False, expand_typedef=False):
- """Recursively expand struct & typedef in place, throw Exception if
+ """Recursively expand struct & typedef in place, throw RuntimeError if
undeclared struct or typedef are used
"""
typ = type(decl)
if typ in (c_ast.Decl, c_ast.TypeDecl, c_ast.PtrDecl, c_ast.ArrayDecl):
- decl.type = _expand_in_place(decl.type, file_ast, expand_struct, expand_typedef)
+ decl.type = _expand_in_place(decl.type, file_ast, expand_struct,
+ expand_typedef)
elif typ == c_ast.Struct:
if not decl.decls:
struct = _find_struct(decl.name, file_ast)
if not struct:
- raise Exception('using undeclared struct %s' % decl.name)
+ raise RuntimeError('using undeclared struct %s' % decl.name)
decl.decls = struct.decls
for i, mem_decl in enumerate(decl.decls):
- decl.decls[i] = _expand_in_place(mem_decl, file_ast, expand_struct, expand_typedef)
-
+ decl.decls[i] = _expand_in_place(mem_decl, file_ast, expand_struct,
+ expand_typedef)
if not expand_struct:
decl.decls = []
@@ -158,7 +163,7 @@
decl.names[0] not in ('int', 'char')):
typedef = _find_typedef(decl.names[0], file_ast)
if not typedef:
- raise Exception('using undeclared type %s' % decl.names[0])
+ raise RuntimeError('using undeclared type %s' % decl.names[0])
if expand_typedef:
return typedef.type
