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Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
"""An implementation of the Zephyr Abstract Syntax Definition Language.
See http://asdl.sourceforge.net/ and
http://www.cs.princeton.edu/~danwang/Papers/dsl97/dsl97-abstract.html.
Only supports top level module decl, not view. I'm guessing that view
is intended to support the browser and I'm not interested in the
browser.
Changes for Python: Add support for module versions
"""
import os
import traceback
import spark
class Token(object):
# spark seems to dispatch in the parser based on a token's
# type attribute
def __init__(self, type, lineno):
self.type = type
self.lineno = lineno
def __str__(self):
return self.type
def __repr__(self):
return str(self)
class Id(Token):
def __init__(self, value, lineno):
self.type = 'Id'
self.value = value
self.lineno = lineno
def __str__(self):
return self.value
class String(Token):
def __init__(self, value, lineno):
self.type = 'String'
self.value = value
self.lineno = lineno
class ASDLSyntaxError(Exception):
def __init__(self, lineno, token=None, msg=None):
self.lineno = lineno
self.token = token
self.msg = msg
def __str__(self):
if self.msg is None:
return "Error at '%s', line %d" % (self.token, self.lineno)
else:
return "%s, line %d" % (self.msg, self.lineno)
class ASDLScanner(spark.GenericScanner, object):
def tokenize(self, input):
self.rv = []
self.lineno = 1
super(ASDLScanner, self).tokenize(input)
return self.rv
def t_id(self, s):
r"[\w\.]+"
# XXX doesn't distinguish upper vs. lower, which is
# significant for ASDL.
self.rv.append(Id(s, self.lineno))
def t_string(self, s):
r'"[^"]*"'
self.rv.append(String(s, self.lineno))
def t_xxx(self, s): # not sure what this production means
r"<="
self.rv.append(Token(s, self.lineno))
def t_punctuation(self, s):
r"[\{\}\*\=\|\(\)\,\?\:]"
self.rv.append(Token(s, self.lineno))
def t_comment(self, s):
r"\-\-[^\n]*"
pass
def t_newline(self, s):
r"\n"
self.lineno += 1
def t_whitespace(self, s):
r"[ \t]+"
pass
def t_default(self, s):
r" . +"
raise ValueError, "unmatched input: %s" % `s`
class ASDLParser(spark.GenericParser, object):
def __init__(self):
super(ASDLParser, self).__init__("module")
def typestring(self, tok):
return tok.type
def error(self, tok):
raise ASDLSyntaxError(tok.lineno, tok)
def p_module_0(self, (module, name, version, _0, _1)):
" module ::= Id Id version { } "
if module.value != "module":
raise ASDLSyntaxError(module.lineno,
msg="expected 'module', found %s" % module)
return Module(name, None, version)
def p_module(self, (module, name, version, _0, definitions, _1)):
" module ::= Id Id version { definitions } "
if module.value != "module":
raise ASDLSyntaxError(module.lineno,
msg="expected 'module', found %s" % module)
return Module(name, definitions, version)
def p_version(self, (version, V)):
"version ::= Id String"
if version.value != "version":
raise ASDLSyntaxError(version.lineno,
msg="expected 'version', found %" % version)
return V
def p_definition_0(self, (definition,)):
" definitions ::= definition "
return definition
def p_definition_1(self, (definitions, definition)):
" definitions ::= definition definitions "
return definitions + definition
def p_definition(self, (id, _, type)):
" definition ::= Id = type "
return [Type(id, type)]
def p_type_0(self, (product,)):
" type ::= product "
return product
def p_type_1(self, (sum,)):
" type ::= sum "
return Sum(sum)
def p_type_2(self, (sum, id, _0, attributes, _1)):
" type ::= sum Id ( fields ) "
if id.value != "attributes":
raise ASDLSyntaxError(id.lineno,
msg="expected attributes, found %s" % id)
if attributes:
attributes.reverse()
return Sum(sum, attributes)
def p_product(self, (_0, fields, _1)):
" product ::= ( fields ) "
# XXX can't I just construct things in the right order?
fields.reverse()
return Product(fields)
def p_sum_0(self, (constructor,)):
" sum ::= constructor "
return [constructor]
def p_sum_1(self, (constructor, _, sum)):
" sum ::= constructor | sum "
return [constructor] + sum
def p_sum_2(self, (constructor, _, sum)):
" sum ::= constructor | sum "
return [constructor] + sum
def p_constructor_0(self, (id,)):
" constructor ::= Id "
return Constructor(id)
def p_constructor_1(self, (id, _0, fields, _1)):
" constructor ::= Id ( fields ) "
# XXX can't I just construct things in the right order?
fields.reverse()
return Constructor(id, fields)
def p_fields_0(self, (field,)):
" fields ::= field "
return [field]
def p_fields_1(self, (field, _, fields)):
" fields ::= field , fields "
return fields + [field]
def p_field_0(self, (type,)):
" field ::= Id "
return Field(type)
def p_field_1(self, (type, name)):
" field ::= Id Id "
return Field(type, name)
def p_field_2(self, (type, _, name)):
" field ::= Id * Id "
return Field(type, name, seq=True)
def p_field_3(self, (type, _, name)):
" field ::= Id ? Id "
return Field(type, name, opt=True)
def p_field_4(self, (type, _)):
" field ::= Id * "
return Field(type, seq=True)
def p_field_5(self, (type, _)):
" field ::= Id ? "
return Field(type, opt=True)
builtin_types = ("identifier", "string", "int", "bool", "object")
# below is a collection of classes to capture the AST of an AST :-)
# not sure if any of the methods are useful yet, but I'm adding them
# piecemeal as they seem helpful
class AST(object):
pass # a marker class
class Module(AST):
def __init__(self, name, dfns, version):
self.name = name
self.dfns = dfns
self.version = version
self.types = {} # maps type name to value (from dfns)
for type in dfns:
self.types[type.name.value] = type.value
def __repr__(self):
return "Module(%s, %s)" % (self.name, self.dfns)
class Type(AST):
def __init__(self, name, value):
self.name = name
self.value = value
def __repr__(self):
return "Type(%s, %s)" % (self.name, self.value)
class Constructor(AST):
def __init__(self, name, fields=None):
self.name = name
self.fields = fields or []
def __repr__(self):
return "Constructor(%s, %s)" % (self.name, self.fields)
class Field(AST):
def __init__(self, type, name=None, seq=False, opt=False):
self.type = type
self.name = name
self.seq = seq
self.opt = opt
def __repr__(self):
if self.seq:
extra = ", seq=True"
elif self.opt:
extra = ", opt=True"
else:
extra = ""
if self.name is None:
return "Field(%s%s)" % (self.type, extra)
else:
return "Field(%s, %s%s)" % (self.type, self.name, extra)
class Sum(AST):
def __init__(self, types, attributes=None):
self.types = types
self.attributes = attributes or []
def __repr__(self):
if self.attributes is None:
return "Sum(%s)" % self.types
else:
return "Sum(%s, %s)" % (self.types, self.attributes)
class Product(AST):
def __init__(self, fields):
self.fields = fields
def __repr__(self):
return "Product(%s)" % self.fields
class VisitorBase(object):
def __init__(self, skip=False):
self.cache = {}
self.skip = skip
def visit(self, object, *args):
meth = self._dispatch(object)
if meth is None:
return
try:
meth(object, *args)
except Exception, err:
print "Error visiting", repr(object)
print err
traceback.print_exc()
# XXX hack
if hasattr(self, 'file'):
self.file.flush()
os._exit(1)
def _dispatch(self, object):
assert isinstance(object, AST), repr(object)
klass = object.__class__
meth = self.cache.get(klass)
if meth is None:
methname = "visit" + klass.__name__
if self.skip:
meth = getattr(self, methname, None)
else:
meth = getattr(self, methname)
self.cache[klass] = meth
return meth
class Check(VisitorBase):
def __init__(self):
super(Check, self).__init__(skip=True)
self.cons = {}
self.errors = 0
self.types = {}
def visitModule(self, mod):
for dfn in mod.dfns:
self.visit(dfn)
def visitType(self, type):
self.visit(type.value, str(type.name))
def visitSum(self, sum, name):
for t in sum.types:
self.visit(t, name)
def visitConstructor(self, cons, name):
key = str(cons.name)
conflict = self.cons.get(key)
if conflict is None:
self.cons[key] = name
else:
print "Redefinition of constructor %s" % key
print "Defined in %s and %s" % (conflict, name)
self.errors += 1
for f in cons.fields:
self.visit(f, key)
def visitField(self, field, name):
key = str(field.type)
l = self.types.setdefault(key, [])
l.append(name)
def visitProduct(self, prod, name):
for f in prod.fields:
self.visit(f, name)
def check(mod):
v = Check()
v.visit(mod)
for t in v.types:
if t not in mod.types and not t in builtin_types:
v.errors += 1
uses = ", ".join(v.types[t])
print "Undefined type %s, used in %s" % (t, uses)
return not v.errors
def parse(file):
scanner = ASDLScanner()
parser = ASDLParser()
buf = open(file).read()
tokens = scanner.tokenize(buf)
try:
return parser.parse(tokens)
except ASDLSyntaxError, err:
print err
lines = buf.split("\n")
print lines[err.lineno - 1] # lines starts at 0, files at 1
if __name__ == "__main__":
import glob
import sys
if len(sys.argv) > 1:
files = sys.argv[1:]
else:
testdir = "tests"
files = glob.glob(testdir + "/*.asdl")
for file in files:
print file
mod = parse(file)
print "module", mod.name
print len(mod.dfns), "definitions"
if not check(mod):
print "Check failed"
else:
for dfn in mod.dfns:
print dfn.type