-
Notifications
You must be signed in to change notification settings - Fork 12
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Refactor code into macro and funcs implementations
- Loading branch information
1 parent
bbd4fe1
commit 5b492d0
Showing
8 changed files
with
481 additions
and
428 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -1,360 +1,21 @@ | ||
| """ | ||
| # PyPatt - Python Pattern Matching | ||
| ## Development | ||
| """# PyPatt | ||
| * `uncompile`, `recompile`, and `parse_snippet` based on | ||
| http://code.activestate.com/recipes/578353-code-to-source-and-back/ | ||
| Written by Oren Tirosh. Dec 1, 2012. Shared with MIT License. | ||
| * An AST pretty-printer can be pretty useful. I had good luck | ||
| with https://pypi.python.org/pypi/astunparse/ | ||
| """ | ||
|
|
||
| import ast, inspect, re | ||
| from itertools import count, izip as zip | ||
| from functools import partial | ||
| from types import CodeType, FunctionType | ||
|
|
||
| import __future__ | ||
| PyCF_MASK = sum(val for key, val in vars(__future__).items() | ||
| if key.startswith('CO_FUTURE')) | ||
|
|
||
| def uncompile(cobj): | ||
| if cobj.co_flags & inspect.CO_NESTED or cobj.co_freevars: | ||
| raise RuntimeError('nested functions not supported') | ||
| if cobj.co_name == '<lambda>': | ||
| raise RuntimeError('lambda functions not supported') | ||
| if cobj.co_filename == '<string>': | ||
| raise RuntimeError('code without source file not supported') | ||
|
|
||
| filename = inspect.getfile(cobj) | ||
| lines, firstlineno = inspect.getsourcelines(cobj) | ||
| source = ''.join(lines) | ||
|
|
||
| # Find the mangled name (__X -> _ClassName__X) if present. | ||
|
|
||
| privateprefix = None | ||
|
|
||
| for name in cobj.co_names: | ||
| match = re.match('^(_[A-Za-z0-9][A-Za-z0-9_]*)__.*$', name) | ||
| if match: | ||
| privateprefix = match.group(1) | ||
| break | ||
|
|
||
| flags = cobj.co_flags & PyCF_MASK | ||
|
|
||
| return source, filename, 'exec', flags, firstlineno, privateprefix | ||
|
|
||
| def recompile(source, filename, mode, flags=0, lineno=1, prefix=None): | ||
| if isinstance(source, ast.AST): | ||
| root = source | ||
| else: | ||
| root = parse_snippet(source, filename, mode, flags, lineno) | ||
|
|
||
| node = root.body[0] | ||
|
|
||
| if not isinstance(node, ast.FunctionDef): | ||
| raise RuntimeError('expected FunctionDef AST node') | ||
|
|
||
| code = compile(root, filename, mode, flags, True) | ||
|
|
||
| for cobj in code.co_consts: | ||
| if not isinstance(cobj, CodeType): | ||
| continue | ||
| if cobj.co_name == node.name and cobj.co_firstlineno == node.lineno: | ||
| break | ||
| else: | ||
| raise RuntimeError('function code not found') | ||
|
|
||
| # Mangle private names if necessary. | ||
|
|
||
| if prefix is not None: | ||
|
|
||
| is_private = re.compile('^__.*(?<!__)$').match | ||
|
|
||
| def fix_names(names): | ||
| return tuple( | ||
| prefix + name if is_private(name) else name for name in names | ||
| ) | ||
|
|
||
| cobj = CodeType( | ||
| cobj.co_argcount, | ||
| cobj.co_nlocals, | ||
| cobj.co_stacksize, | ||
| cobj.co_flags, | ||
| cobj.co_code, | ||
| cobj.co_consts, | ||
| fix_names(cobj.co_names), | ||
| fix_names(cobj.co_varnames), | ||
| cobj.co_filename, | ||
| cobj.co_name, | ||
| cobj.co_firstlineno, | ||
| cobj.co_lnotab, | ||
| cobj.co_freevars, | ||
| cobj.co_cellvars | ||
| ) | ||
|
|
||
| return cobj | ||
|
|
||
| def parse_snippet(source, filename, mode, flags, firstlineno): | ||
| args = filename, mode, flags | ast.PyCF_ONLY_AST, True | ||
|
|
||
| try: | ||
| code = compile('\n' + source, *args) | ||
| except IndentationError: | ||
| code = compile('with 0:\n' + source, *args) | ||
| code.body = code.body[0].body | ||
|
|
||
| ast.increment_lineno(code, firstlineno - 2) | ||
|
|
||
| return code | ||
|
|
||
| store = dict() | ||
|
|
||
| class PyPattBreak(Exception): | ||
| pass | ||
|
|
||
| def bind(quote, expr, value, globs, locs): | ||
| names = set(QuotedVarsVisitor(quote)(expr)) | ||
| bound = {} | ||
|
|
||
| class Mismatch(Exception): | ||
| pass | ||
|
|
||
| def visitor(node, value): | ||
| if isinstance(node, ast.List): | ||
| if isinstance(value, list) and len(value) == len(node.elts): | ||
| return list(visitor(lhs, rhs) | ||
| for lhs, rhs in zip(node.elts, value)) | ||
| else: | ||
| raise Mismatch | ||
| elif isinstance(node, ast.Tuple): | ||
| if isinstance(value, tuple) and len(value) == len(node.elts): | ||
| return tuple(visitor(lhs, rhs) | ||
| for lhs, rhs in zip(node.elts, value)) | ||
| else: | ||
| raise Mismatch | ||
| elif isinstance(node, ast.Num): | ||
| if not isinstance(value, (int, float, long)): | ||
| raise Mismatch | ||
| if value != node.n: | ||
| raise Mismatch | ||
| return value | ||
| elif isinstance(node, ast.Str): | ||
| if not isinstance(value, (str, unicode)): | ||
| raise Mismatch | ||
| if value != node.s: | ||
| raise Mismatch | ||
| return value | ||
| elif isinstance(node, ast.Name): | ||
| if node.id in locs: | ||
| if value != locs[node.id]: | ||
| raise Mismatch | ||
| elif node.id in globs: | ||
| if value != globs[node.id]: | ||
| raise Mismatch | ||
| elif node.id in ('True', 'False'): | ||
| if value != (node.id == 'True'): | ||
| raise Mismatch | ||
| else: | ||
| raise RuntimeError('unknown ast.Name') | ||
| return value | ||
| elif isinstance(node, ast.Call): | ||
| name = is_call_quote(node, quote) | ||
| if not name: | ||
| raise RuntimeError('unknown ast.Call') | ||
| if name in bound: | ||
| if value != bound[name]: | ||
| raise Mismatch | ||
| else: | ||
| bound[name] = value | ||
| return value | ||
| else: | ||
| raise RuntimeError('unknown ast.Node') | ||
|
|
||
| try: | ||
| result = visitor(expr, value) | ||
| return (result, bound) | ||
| except Mismatch: | ||
| return False | ||
|
|
||
| def is_call_quote(node, quote): | ||
| if not isinstance(node.func, ast.Name): | ||
| return False | ||
| if node.func.id != quote: | ||
| return False | ||
| if len(node.args) != 1: | ||
| return False | ||
| if not isinstance(node.args[0], ast.Name): | ||
| return False | ||
| if len(node.keywords): | ||
| return False | ||
| if node.starargs is not None: | ||
| return False | ||
| if node.kwargs is not None: | ||
| return False | ||
| return node.args[0].id | ||
|
|
||
| class QuotedVarsVisitor(ast.NodeVisitor): | ||
| def __init__(self, quote): | ||
| self.names = [] | ||
| self.quote = quote | ||
| def visit_Call(self, node): | ||
| name = is_call_quote(node, self.quote) | ||
| if name: | ||
| self.names.append(name) | ||
| self.generic_visit(node) | ||
| def __call__(self, node): | ||
| self.visit(node) | ||
| return self.names | ||
|
|
||
| def is_with_match(node, match): | ||
| expr = node.context_expr | ||
| if not isinstance(expr, ast.Call): | ||
| return False | ||
| if not isinstance(expr.func, ast.Name): | ||
| return False | ||
| if expr.func.id != match: | ||
| return False | ||
| if len(expr.args) != 1: | ||
| return False | ||
| if len(expr.keywords): | ||
| return False | ||
| if expr.starargs is not None: | ||
| return False | ||
| if expr.kwargs is not None: | ||
| return False | ||
| return expr.args[0] | ||
|
|
||
| counter = count() | ||
|
|
||
| class MatchTransformVisitor(ast.NodeTransformer): | ||
| def __init__(self, match='match', quote='quote', module='pypatt'): | ||
| self.count = counter | ||
| self.module = module | ||
| self.match = match | ||
| self.quote = quote | ||
|
|
||
| def temp_name(self): | ||
| return 'pypatt_temp_' + str(next(self.count)) | ||
|
|
||
| def visit_With(self, node): | ||
| expr = is_with_match(node, self.match) | ||
|
|
||
| if expr is False: | ||
| return self.generic_visit(node) | ||
|
|
||
| if not all(isinstance(subnode, ast.With) | ||
| and is_with_match(subnode, self.match) is False | ||
| for subnode in node.body): | ||
| msg = ( | ||
| 'statements in `with {0}(...) ...` must all' | ||
| ' be `with` statements' | ||
| ) | ||
| raise RuntimeError(msg.format(self.match)) | ||
|
|
||
| stmt = ast.parse( | ||
| 'try:\n pass\nexcept {module}.PyPattBreak:\n pass'.format( | ||
| module=self.module | ||
| ) | ||
| ).body[0] | ||
| del stmt.body[0] | ||
|
|
||
| temp_match = self.temp_name() | ||
|
|
||
| assign_expr = ast.Assign( | ||
| targets=[ast.Name(id=temp_match, ctx=ast.Store())], | ||
| value=expr | ||
| ) | ||
|
|
||
| stmt.body.append(assign_expr) | ||
|
|
||
| if node.optional_vars: | ||
| stmt.body.append(ast.parse( | ||
| '{name} = {temp_match}'.format( | ||
| name=node.optional_vars.id, | ||
| temp_match=temp_match, | ||
| ) | ||
| ).body[0]) | ||
|
|
||
| for with_stmt in node.body: | ||
| temp_ast = self.temp_name() | ||
| temp_store = self.temp_name() | ||
| with_expr = with_stmt.context_expr | ||
|
|
||
| store[temp_store] = with_expr | ||
|
|
||
| stmt.body.append(ast.parse( | ||
| '{temp_ast} = {module}.store["{temp_store}"]'.format( | ||
| temp_ast=temp_ast, | ||
| module=self.module, | ||
| temp_store=temp_store | ||
| ) | ||
| ).body[0]) | ||
|
|
||
| temp_vars = self.temp_name() | ||
|
|
||
| stmt.body.append(ast.parse( | ||
| ('{temp_vars} = {module}.bind("{quote}", ' | ||
| '{temp_ast}, {temp_match}, globals(), locals())').format( | ||
| quote=self.quote, | ||
| temp_vars=temp_vars, | ||
| module=self.module, | ||
| temp_match=temp_match, | ||
| temp_ast=temp_ast | ||
| ) | ||
| ).body[0]) | ||
|
|
||
| if_stmt = ast.If( | ||
| test=ast.Name(id=temp_vars, ctx=ast.Load()), | ||
| body=[], orelse=[] | ||
| ) | ||
|
|
||
| stmt.body.append(if_stmt) | ||
|
|
||
| if with_stmt.optional_vars: | ||
| if_stmt.body.append(ast.parse( | ||
| '{name} = {temp_vars}[0]'.format( | ||
| name=with_stmt.optional_vars.id, | ||
| temp_vars=temp_vars | ||
| ) | ||
| ).body[0]) | ||
|
|
||
| quoted_vars = QuotedVarsVisitor(self.quote)(with_expr) | ||
|
|
||
| for var in quoted_vars: | ||
| if_stmt.body.append(ast.parse( | ||
| '{var} = {temp_vars}[1]["{var}"]'.format( | ||
| var=var, | ||
| temp_vars=temp_vars | ||
| ) | ||
| ).body[0]) | ||
|
|
||
| if_stmt.body.extend(self.visit(temp) for temp in with_stmt.body) | ||
| from sys import hexversion as _hexversion | ||
| from platform import python_implementation as _python_implementation | ||
|
|
||
| if_stmt.body.append(ast.parse( | ||
| 'raise {module}.PyPattBreak'.format(module=self.module) | ||
| ).body[0]) | ||
| _cpython = (_python_implementation() == 'CPython') | ||
| _cpython2 = (_cpython and 0x02060000 <= _hexversion < 0x02080000) | ||
|
|
||
| return stmt | ||
| if _cpython2: | ||
| from .macro import store, transform, uncompile, recompile, PyPattBreak, trybind | ||
|
|
||
| def transform(func=None, visitor=MatchTransformVisitor, **kwargs): | ||
| if func is None: | ||
| return partial(transform, visitor=visitor, **kwargs) | ||
| else: | ||
| parts = list(uncompile(func.func_code)) | ||
| root = parse_snippet(*parts[:-1]) | ||
| root = visitor(**kwargs).visit(root) | ||
| ast.fix_missing_locations(root) | ||
| parts[0] = root | ||
| # import astunparse | ||
| # print astunparse.unparse(root) | ||
| func.func_code = recompile(*parts) | ||
| return func | ||
| from .funcs import match, bind, bound, like | ||
|
|
||
| __title__ = 'pypatt' | ||
| __version__ = '0.1.1' | ||
| __build__ = 0x000100 | ||
| __version__ = '0.2.0' | ||
| __build__ = 0x000200 | ||
| __author__ = 'Grant Jenks' | ||
| __license__ = 'Apache 2.0' | ||
| __copyright__ = 'Copyright 2015 Grant Jenks' |
Oops, something went wrong.