def from_AST(cls, node, factory):
"""Construct from an Enumerator node of form
<vars> in <rel>
Alternatively, the rhs may be a setmatch of a rel, where
the mask is a lookupmask and the key is a vartuple.
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
rhs = node.iter
if L.is_name(rhs):
rel = L.get_name(rhs)
elif isinstance(rhs, L.SetMatch) and L.is_vartuple(rhs.key):
keyvars = L.get_vartuple(rhs.key)
# Make sure we're dealing with a lookupmask and that the
# key vars agree with the mask.
mask = Mask(rhs.mask)
assert mask.is_lookupmask
assert mask.lookup_arity == len(keyvars)
lhs = keyvars + lhs
rel = L.get_name(rhs.target)
else:
raise TypeError
return cls(lhs, rel)
def from_comp(cls, node, factory):
"""Construct from Comp node. Requires a ClauseFactory."""
checktype(node, L.Comp)
join = Join.from_comp(node, factory)
return cls(join, node.resexp, node.params)
def from_AST(cls, node, factory):
"""Construct from an Enumerator node of form
<vars> in <rel>
Alternatively, the rhs may be a setmatch of a rel, where
the mask is a lookupmask and the key is a vartuple.
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
rhs = node.iter
if L.is_name(rhs):
rel = L.get_name(rhs)
elif isinstance(rhs, L.SetMatch) and L.is_vartuple(rhs.key):
keyvars = L.get_vartuple(rhs.key)
# Make sure we're dealing with a lookupmask and that the
# key vars agree with the mask.
mask = Mask(rhs.mask)
assert mask.is_lookupmask
assert mask.lookup_arity == len(keyvars)
lhs = keyvars + lhs
rel = L.get_name(rhs.target)
else:
raise TypeError
return cls(lhs, rel)
def from_comp(cls, node, factory):
"""Construct from Comp node, ignoring the result expression.
factory is used to construct clauses from their ASTs.
"""
checktype(node, L.Comp)
clauses = [factory.from_AST(clast) for clast in node.clauses]
delta = DeltaInfo.from_options(node.options)
return cls(clauses, factory, delta)
def from_comp(cls, node, factory):
"""Construct from Comp node, ignoring the result expression.
factory is used to construct clauses from their ASTs.
"""
checktype(node, L.Comp)
clauses = [factory.from_AST(clast) for clast in node.clauses]
delta = DeltaInfo.from_options(node.options)
return cls(clauses, factory, delta)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in {<expr>}
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
val = L.get_singletonset(node.iter)
return cls(lhs, val)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in {<expr>}
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
val = L.get_singletonset(node.iter)
return cls(lhs, val)
def from_expr(cls, node):
"""Construct from a condition expression of form
<vars> == <rel>
"""
checktype(node, L.AST)
left, op, val = L.get_cmp(node)
checktype(op, L.Eq)
lhs = L.get_vartuple(left)
return cls(lhs, val)
def from_expr(cls, node):
"""Construct from a condition expression of form
<vars> == <rel>
"""
checktype(node, L.AST)
left, op, val = L.get_cmp(node)
checktype(op, L.Eq)
lhs = L.get_vartuple(left)
return cls(lhs, val)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in <rel> + {<expr>}
"""
checktype(node, L.Enumerator)
rhs, extra = L.get_singadd(node.iter)
innernode = node._replace(iter=rhs)
innerclause = factory.from_AST(innernode)
return cls(innerclause, extra)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in <rel> + {<expr>}
"""
checktype(node, L.Enumerator)
rhs, extra = L.get_singadd(node.iter)
innernode = node._replace(iter=rhs)
innerclause = factory.from_AST(innernode)
return cls(innerclause, extra)
def from_expr(cls, node):
"""Construct from a membership condition expression of form
<vars> in <rel>
Note that this is syntactically different from the form used
in comprehensions, even though their textual representation
in source code is the same.
"""
checktype(node, L.AST)
left, op, right = L.get_cmp(node)
checktype(op, L.In)
lhs = L.get_vartuple(left)
rel = L.get_name(right)
return cls(lhs, rel)
def from_expr(cls, node):
"""Construct from a membership condition expression of form
<vars> in <rel>
Note that this is syntactically different from the form used
in comprehensions, even though their textual representation
in source code is the same.
"""
checktype(node, L.AST)
left, op, right = L.get_cmp(node)
checktype(op, L.In)
lhs = L.get_vartuple(left)
rel = L.get_name(right)
return cls(lhs, rel)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in deltamatch(<rel>, <mask>, <val>, <limit>)
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
checktype(node.iter, L.DeltaMatch)
rel = L.get_name(node.iter.target)
mask = Mask(node.iter.mask)
val = node.iter.elem
limit = node.iter.limit
if limit not in [0, 1]:
raise TypeError
inferred_mask = Mask.from_vars(lhs, lhs)
assert mask == inferred_mask
return cls(lhs, rel, val, limit)
def from_AST(cls, node, factory):
"""Construct from Enumerator node of form
<vars> in deltamatch(<rel>, <mask>, <val>, <limit>)
"""
checktype(node, L.Enumerator)
lhs = L.get_vartuple(node.target)
checktype(node.iter, L.DeltaMatch)
rel = L.get_name(node.iter.target)
mask = Mask(node.iter.mask)
val = node.iter.elem
limit = node.iter.limit
if limit not in [0, 1]:
raise TypeError
inferred_mask = Mask.from_vars(lhs, lhs)
assert mask == inferred_mask
return cls(lhs, rel, val, limit)
def from_AST(cls, node, factory):
"""Construct from an Enumerator node of form
var in {<rel>.smlookup(<mask>, <key vars>)}
"""
checktype(node, L.Enumerator)
var = L.get_name(node.target)
sm = L.get_singletonset(node.iter)
checktype(sm, L.SMLookup)
rel = L.get_name(sm.target)
mask = Mask(sm.mask)
keyvars = L.get_vartuple(sm.key)
# Ensure the mask is consistent with how it's used.
if mask != Mask.from_keylen(len(keyvars)):
raise TypeError
lhs = keyvars + (var,)
return cls(lhs, rel)
def from_AST(cls, node, factory):
"""Construct from an Enumerator node of form
var in {<rel>.smlookup(<mask>, <key vars>)}
"""
checktype(node, L.Enumerator)
var = L.get_name(node.target)
sm = L.get_singletonset(node.iter)
checktype(sm, L.SMLookup)
rel = L.get_name(sm.target)
mask = Mask(sm.mask)
keyvars = L.get_vartuple(sm.key)
# Ensure the mask is consistent with how it's used.
if mask != Mask.from_keylen(len(keyvars)):
raise TypeError
lhs = keyvars + (var, )
return cls(lhs, rel)
def from_AST(cls, node, factory):
"""Construct from expression node."""
checktype(node, L.expr)
return cls(node)
def from_AST(cls, node, factory):
"""Construct from expression node."""
checktype(node, L.expr)
return cls(node)