1 | #!/usr/bin/env python
|
2 | """
|
3 | gen_python.py
|
4 |
|
5 | Generate Python code from and ASDL schema.
|
6 |
|
7 | TODO:
|
8 | - What about Id? app_types?
|
9 | """
|
10 |
|
11 | import sys
|
12 |
|
13 | from asdl import asdl_ as asdl
|
14 | from asdl import visitor
|
15 |
|
16 |
|
17 | class GenClassesVisitor(visitor.AsdlVisitor):
|
18 |
|
19 | def VisitSimpleSum(self, sum, name, depth):
|
20 | self.Emit('class %s_e(py_meta.SimpleObj):' % name, depth)
|
21 | self.Emit(' ASDL_TYPE = TYPE_LOOKUP.ByTypeName(%r)' % name, depth)
|
22 | self.Emit('', depth)
|
23 |
|
24 | # Just use #define, since enums aren't namespaced.
|
25 | for i, variant in enumerate(sum.types):
|
26 | attr = '%s_e.%s = %s_e(%d, %r)' % (
|
27 | name, variant.name, name, i + 1, variant.name)
|
28 | self.Emit(attr, depth)
|
29 | self.Emit('', depth)
|
30 |
|
31 | def _GenClass(self, desc, name, super_name, depth, tag_num=None):
|
32 | self.Emit('class %s(%s):' % (name, super_name), depth)
|
33 |
|
34 | if tag_num is not None:
|
35 | self.Emit(' tag = %d' % tag_num, depth)
|
36 |
|
37 | field_names = [f.name for f in desc.fields]
|
38 |
|
39 | quoted_fields = repr(tuple(field_names))
|
40 | # NOTE: FIELDS is a duplicate of __slots__, used for pretty printing and
|
41 | # oheap serialization. TODO: measure the effect of __slots__, and then get
|
42 | # rid of FIELDS? Or you can just make it an alias.
|
43 | # FIELDS = self.__slots__.
|
44 | self.Emit(' ASDL_TYPE = TYPE_LOOKUP.ByTypeName(%r)' % name, depth)
|
45 | self.Emit(' __slots__ = %s' % quoted_fields, depth)
|
46 |
|
47 | self.Emit('', depth)
|
48 |
|
49 | # TODO: leave out spids? Mark it as an attribute?
|
50 | args = ', '.join('%s=None' % f.name for f in desc.fields)
|
51 | self.Emit(' def __init__(self, %s):' % args, depth)
|
52 |
|
53 | for f in desc.fields:
|
54 | # This logic is like _MakeFieldDescriptors
|
55 | default = None
|
56 | if f.opt: # Maybe
|
57 | if f.type == 'int':
|
58 | default = 'const.NO_INTEGER'
|
59 | elif f.type == 'string':
|
60 | default = "''"
|
61 | else:
|
62 | default = 'None'
|
63 |
|
64 | elif f.seq: # Array
|
65 | default = '[]'
|
66 |
|
67 | # PROBLEM: Optional ints can't be zero!
|
68 | # self.span_id = span_id or const.NO_INTEGER
|
69 | # I don't want to add if statements checking against None?
|
70 | # For now don't use optional ints. We don't need it.
|
71 |
|
72 | default_str = (' or %s' % default) if default else ''
|
73 | self.Emit(' self.%s = %s%s' % (f.name, f.name, default_str), depth)
|
74 |
|
75 | self.Emit('', depth)
|
76 |
|
77 | def VisitConstructor(self, cons, def_name, tag_num, depth):
|
78 | if cons.fields:
|
79 | self._GenClass(cons, cons.name, def_name, depth, tag_num=tag_num)
|
80 | else:
|
81 | self.Emit("class %s(%s):" % (cons.name, def_name), depth)
|
82 | self.Emit(' ASDL_TYPE = TYPE_LOOKUP.ByTypeName(%r)' % cons.name, depth)
|
83 | self.Emit(' tag = %d' % tag_num, depth)
|
84 | self.Emit('', depth)
|
85 |
|
86 | def VisitCompoundSum(self, sum, name, depth):
|
87 | # define command_e
|
88 | self.Emit('class %s_e(object):' % name, depth)
|
89 | for i, variant in enumerate(sum.types):
|
90 | self.Emit(' %s = %d' % (variant.name, i + 1), depth)
|
91 | self.Emit('', depth)
|
92 |
|
93 | self.Emit('class %s(py_meta.CompoundObj):' % name, depth)
|
94 | self.Emit(' ASDL_TYPE = TYPE_LOOKUP.ByTypeName(%r)' % name, depth)
|
95 | self.Emit('', depth)
|
96 |
|
97 | # define command_t, and then make subclasses
|
98 | super_name = '%s' % name
|
99 | for i, t in enumerate(sum.types):
|
100 | tag_num = i + 1
|
101 | self.VisitConstructor(t, super_name, tag_num, depth)
|
102 |
|
103 | def VisitProduct(self, product, name, depth):
|
104 | self._GenClass(product, name, 'py_meta.CompoundObj', depth)
|
105 |
|
106 | def EmitFooter(self):
|
107 | pass
|
108 |
|
109 |
|
110 | def main(argv):
|
111 |
|
112 | schema_path = argv[1]
|
113 | type_lookup_import = argv[2]
|
114 | with open(schema_path) as input_f:
|
115 | module = asdl.parse(input_f)
|
116 |
|
117 | f = sys.stdout
|
118 |
|
119 | f.write("""\
|
120 | from asdl import const # For const.NO_INTEGER
|
121 | from asdl import py_meta
|
122 | %s
|
123 |
|
124 | """ % type_lookup_import)
|
125 |
|
126 | v = GenClassesVisitor(f)
|
127 | v.VisitModule(module)
|
128 |
|
129 |
|
130 | if __name__ == '__main__':
|
131 | try:
|
132 | main(sys.argv)
|
133 | except RuntimeError as e:
|
134 | print >>sys.stderr, 'FATAL: %s' % e
|
135 | sys.exit(1)
|