home *** CD-ROM | disk | FTP | other *** search
- # Source Generated with Decompyle++
- # File: in.pyc (Python 2.4)
-
- '''Parser for future statements
-
- '''
- from compiler import ast, walk
-
- def is_future(stmt):
- '''Return true if statement is a well-formed future statement'''
- if not isinstance(stmt, ast.From):
- return 0
-
- if stmt.modname == '__future__':
- return 1
- else:
- return 0
-
-
- class FutureParser:
- features = ('nested_scopes', 'generators', 'division')
-
- def __init__(self):
- self.found = { }
-
-
- def visitModule(self, node):
- stmt = node.node
- for s in stmt.nodes:
- if not self.check_stmt(s):
- break
- continue
-
-
-
- def check_stmt(self, stmt):
- if is_future(stmt):
- for name, asname in stmt.names:
- if name in self.features:
- self.found[name] = 1
- continue
- raise SyntaxError, 'future feature %s is not defined' % name
-
- stmt.valid_future = 1
- return 1
-
- return 0
-
-
- def get_features(self):
- '''Return list of features enabled by future statements'''
- return self.found.keys()
-
-
-
- class BadFutureParser:
- '''Check for invalid future statements'''
-
- def visitFrom(self, node):
- if hasattr(node, 'valid_future'):
- return None
-
- if node.modname != '__future__':
- return None
-
- raise SyntaxError, 'invalid future statement'
-
-
-
- def find_futures(node):
- p1 = FutureParser()
- p2 = BadFutureParser()
- walk(node, p1)
- walk(node, p2)
- return p1.get_features()
-
- if __name__ == '__main__':
- import sys
- from compiler import parseFile, walk
- for file in sys.argv[1:]:
- print file
- tree = parseFile(file)
- v = FutureParser()
- walk(tree, v)
- print v.found
- print
-
-
-