How to use the gast.Constant function in gast
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serge-sans-paille / pythran / pythran / optimizations / modindex.py View on Github 
range_ = alias
else:
break
if range_ is None:
return self.generic_visit(node)
# everything is setup for the transformation!
new_id = node.left.id + '_m'
i = 0
while new_id in self.identifiers:
new_id = '{}_m{}'.format(node.left.id, i)
i += 1
rargs = range_.args.args
lower = rargs[0] if len(rargs) > 1 else ast.Constant(0, None)
header = ast.Assign([ast.Name(new_id, ast.Store(), None, None)],
ast.BinOp(
ast.BinOp(deepcopy(lower),
ast.Sub(),
ast.Constant(1, None)),
ast.Mod(),
deepcopy(node.right)))
incr = ast.BinOp(ast.Name(new_id, ast.Load(), None, None),
ast.Add(),
ast.Constant(1, None))
step = ast.Assign([ast.Name(new_id, ast.Store(), None, None)],
ast.IfExp(
ast.Compare(incr,
[ast.Eq()], [deepcopy(node.right)]),
ast.Constant(0, None),
deepcopy(incr)))import numpy as __pythran_import_numpy
__pythran_import_numpy.square(a)
>>> node = ast.parse('__pythran_import_numpy.power(a,2)')
>>> pm = passmanager.PassManager("test")
>>> _, node = pm.apply(Square, node)
>>> print(pm.dump(backend.Python, node))
import numpy as __pythran_import_numpy
__pythran_import_numpy.square(a)
"""
POW_PATTERN = ast.BinOp(AST_any(), ast.Pow(), ast.Constant(2, None))
POWER_PATTERN = ast.Call(
ast.Attribute(ast.Name(mangle('numpy'), ast.Load(), None, None),
'power',
ast.Load()),
[AST_any(), ast.Constant(2, None)],
[])
def __init__(self):
Transformation.__init__(self)
def replace(self, value):
self.update = self.need_import = True
module_name = ast.Name(mangle('numpy'), ast.Load(), None, None)
return ast.Call(ast.Attribute(module_name, 'square', ast.Load()),
[value], [])
def visit_Module(self, node):
self.need_import = False
self.generic_visit(node)
if self.need_import:
import_alias = ast.alias(name='numpy', asname=mangle('numpy'))def make_array_index(self, base, size, index):
if isinstance(base, ast.Constant):
return ast.Constant(base.value, None)
if size == 1:
return deepcopy(base.elts[0])
return base.elts[index]def is_none(expr):
# py3
if isinstance(expr, ast.Constant) and expr.value is None:
return True
# py2
if not isinstance(expr, ast.Attribute):
return False
return expr.attr == "None"def sub():
return ast.BinOp(left=Placeholder(0), op=ast.Pow(),
right=ast.Constant(2, None))def handle_special_calls(func_alias, node):
if func_alias is MODULES['numpy']['arange']:
if len(node.args) == 1:
node.args.insert(0, ast.Constant(0, None))if not isinstance(node.value, ast.Subscript):
return node
if not isinstance(node.value.slice, ast.Slice):
return node
if not isinstance(node.slice, ast.Index):
return node
if not isnum(node.slice.value):
return node
slice_ = node.value.slice
index = node.slice
node = node.value
node.slice = index
lower = slice_.lower or ast.Constant(0, None)
step = slice_.step or ast.Constant(1, None)
node.slice.value = ast.BinOp(lower,
ast.Add(),
ast.BinOp(index.value,
ast.Mult(),
step))
self.update = True
return node @staticmethod
def sub():
return ast.Call(
func=ast.Attribute(value=ast.Name(id=mangle('numpy'),
ctx=ast.Load(),
annotation=None,
type_comment=None),
attr="sqrt", ctx=ast.Load()),
args=[Placeholder(0)], keywords=[])
extra_imports = [ast.Import([ast.alias('numpy', mangle('numpy'))])]
class CbrtPattern(Pattern):
# X ** .33333 => numpy.cbrt(X)
pattern = ast.BinOp(Placeholder(0), ast.Pow(), ast.Constant(1./3., None))
@staticmethod
def sub():
return ast.Call(
func=ast.Attribute(value=ast.Name(id=mangle('numpy'),
ctx=ast.Load(),
annotation=None,
type_comment=None),
attr="cbrt", ctx=ast.Load()),
args=[Placeholder(0)], keywords=[])
extra_imports = [ast.Import([ast.alias('numpy', mangle('numpy'))])]
class TuplePattern(Pattern):
# __builtin__.tuple([X, ..., Z]) => (X, ..., Z)lambda x, y: ast.Subscript(
x,
ast.Index(ast.Constant(y, None)),
ast.Load()),
state,return None
elif isinstance(nast, gast.Name):
try:
return env.get_var(nast.id)
except NameError as ne:
if nast.id in dir(env.module):
return getattr(env.module, nast.id)
elif nast.id in dir(builtins):
return getattr(builtins, nast.id)
raise
elif isinstance(nast, gast.Constant):
return nast.value
elif isinstance(nast, gast.Expr):
return eval_ast(nast.value, env)
elif isinstance(nast, gast.Constant) and isinstance(nast.value, str):
return nast.value
elif isinstance(nast, gast.Tuple):
return tuple(map(lambda x: eval_ast(x, env), nast.elts))
elif isinstance(nast, gast.List):
return eval_list(nast, env)
elif isinstance(nast, gast.Return):
raise ValueReturn(eval_ast(nast.value, env))
elif isinstance(nast, gast.Assert):
# TODO(hamaji): Emit an assertion?
return None
# TODO(hamaji): Implement `with`.
# elif isinstance(nast, gast.With):
# sys.stderr.write(gast
Python AST that abstracts the underlying Python version
