def test_find_Compare():
expr = parse_expr('a < b < c == e + (f, (gh,))')
found = find_names(expr)
assert len(found) == 6
assert eq(
found, [var('a'), var('b'), var('c'), var('e'), var('f'), var('gh')]
)
def test_find_Compare():
expr = parse_expr('a < b < c == e + (f, (gh,))')
found = find_names(expr)
assert len(found) == 6
assert eq(
found, [var('a'), var('b'), var('c'), var('e'), var('f'), var('gh')]
)
def visit_ListComp(self, node):
"""Generate a curried lambda function
[x + y for x, y in [[1, 4], [2, 5], [3, 6]]]
becomes
[[1, 4], [2, 5], [3, 6]]].map(([x, y]) => x + y)
"""
try:
generator, = node.generators
except ValueError:
raise NotImplementedError(
'Only single loop comprehensions are allowed'
)
names = find_names(generator.target)
argslist = [ast.arg(arg=name.id, annotation=None) for name in names]
if len(names) <= 1:
signature = ast.arguments(
args=argslist,
vararg=None,
kwonlyargs=[],
kw_defaults=[],
kwarg=None,
defaults=[],
)
else:
signature = ast.List(elts=argslist, ctx=ast.Load())
array = generator.iter
lam_sig = functools.partial(ast.Lambda, args=signature)
filters = generator.ifs
if filters:
filt = ast.BoolOp(op=ast.And(), values=filters)
# array.filter
method = ast.Attribute(value=array, attr='filter', ctx=ast.Load())
# array.filter(func)
array = ast.Call(
func=method, args=[lam_sig(body=filt)], keywords=[]
)
method = ast.Attribute(value=array, attr='map', ctx=ast.Load())
mapped = ast.Call(
func=method, args=[lam_sig(body=node.elt)], keywords=[]
)
result = self.visit(mapped)
return result
def visit_ListComp(self, node):
"""Generate a curried lambda function
[x + y for x, y in [[1, 4], [2, 5], [3, 6]]]
becomes
[[1, 4], [2, 5], [3, 6]]].map(([x, y]) => x + y)
"""
try:
generator, = node.generators
except ValueError:
raise NotImplementedError(
'Only single loop comprehensions are allowed'
)
names = find_names(generator.target)
argslist = [ast.arg(arg=name.id, annotation=None) for name in names]
if len(names) <= 1:
signature = ast.arguments(
args=argslist,
vararg=None,
kwonlyargs=[],
kw_defaults=[],
kwarg=None,
defaults=[],
)
else:
signature = ast.List(elts=argslist, ctx=ast.Load())
array = generator.iter
lam_sig = functools.partial(ast.Lambda, args=signature)
filters = generator.ifs
if filters:
filt = ast.BoolOp(op=ast.And(), values=filters)
# array.filter
method = ast.Attribute(value=array, attr='filter', ctx=ast.Load())
# array.filter(func)
array = ast.Call(
func=method, args=[lam_sig(body=filt)], keywords=[]
)
method = ast.Attribute(value=array, attr='map', ctx=ast.Load())
mapped = ast.Call(
func=method, args=[lam_sig(body=node.elt)], keywords=[]
)
result = self.visit(mapped)
return result
def test_find_ListComp():
expr = parse_expr('[i for i in range(n) if i < 2]')
found = find_names(expr)
assert all(isinstance(f, ast.Name) for f in found)
assert eq(found, [var('i'), store('i'), var('n')])
def test_find_Tuple():
expr = parse_expr('(a, (b, 1), (((c,),),))')
found = find_names(expr)
assert len(found) == 3
assert eq(found, [var('a'), var('b'), var('c')])
def test_find_Name():
expr = parse_expr('b')
found = find_names(expr)
assert len(found) == 1
assert eq(found[0], var('b'))
def test_find_dup_names():
expr = parse_expr('a + 1 * a')
found = find_names(expr)
assert len(found) == 1
assert eq(found[0], var('a'))
def test_find_ListComp():
expr = parse_expr('[i for i in range(n) if i < 2]')
found = find_names(expr)
assert all(isinstance(f, ast.Name) for f in found)
assert eq(found, [var('i'), store('i'), var('n')])
def test_find_Tuple():
expr = parse_expr('(a, (b, 1), (((c,),),))')
found = find_names(expr)
assert len(found) == 3
assert eq(found, [var('a'), var('b'), var('c')])
def test_find_Name():
expr = parse_expr('b')
found = find_names(expr)
assert len(found) == 1
assert eq(found[0], var('b'))
def test_find_dup_names():
expr = parse_expr('a + 1 * a')
found = find_names(expr)
assert len(found) == 1
assert eq(found[0], var('a'))
