# The ancestor type for a given superclass
meth ancestor(c: MMLocalClass): MMType
do
- assert _ancestors != null
- if _ancestors.has_key(c) then
- return _ancestors[c].stype
- end
- return null
+ return _ancestors[c].stype
end
end
# The return type
readable attr _return_type: MMType
+ # The closure parameters
+ readable attr _closures: Array[MMClosure] = new Array[MMClosure]
+
# Number of parameters
meth arity: Int
do
return false
end
end
+
+ if closures.length != s.closures.length then return false
+ for i in [0..closures.length[ do
+ if not s.closures[i] < closures[i] then return false
+ end
return true
end
redef meth to_s
do
- var s: String
+ var s = new Buffer
if _params != null and _params.length > 0 then
var tmp: String
var a = new Array[String].with_capacity(_params.length)
#a.add("{pn}: {p}")
a.add(p.to_s)
end
- s = "({a.join(",")})"
- else
- s = ""
+ s.append("({a.join(",")})")
end
if _return_type != null then
s.append(": {_return_type}")
end
- return s
+ return s.to_s
end
# Adapt the signature to a different receiver
if rv != null then
rv = rv.for_module(mod).adapt_to(r)
end
- return new MMSignature(p,rv,r)
+ var res = new MMSignature(p,rv,r)
+ for clos in _closures do
+ res.closures.add(clos.adaptation_to(r))
+ end
+ return res
+ end
+
+ attr _not_for_self_cache: MMSignature = null
+
+ # Return a type approximation if the reveiver is not self
+ # Useful for virtual types
+ meth not_for_self: MMSignature
+ do
+ var res = _not_for_self_cache
+ if res != null then return res
+
+ var need_for_self = false
+ var p = _params
+ if p != null then
+ p = new Array[MMType]
+ for i in _params do
+ var i2 = i.not_for_self
+ if i != i2 then need_for_self = true
+ p.add(i2)
+ end
+ end
+
+ var rv = _return_type
+ if rv != null then
+ rv = rv.not_for_self
+ if rv != _return_type then need_for_self = true
+ end
+
+ var clos = _closures
+ if clos != null then
+ clos = new Array[MMClosure]
+ for c in _closures do
+ var c2 = c.not_for_self
+ if c2 != c then need_for_self = true
+ clos.add(c2)
+ end
+ end
+
+ if need_for_self then
+ res = new MMSignature(p, rv, _recv)
+ res.closures.add_all(clos)
+ else
+ res = self
+ end
+
+ _not_for_self_cache = res
+ return res
end
init(params: Array[MMType], return_type: MMType, r: MMType)
end
end
+# A closure in a signature
+class MMClosure
+ # The signature of the closure
+ readable attr _signature: MMSignature
+
+ # Is the closure a brek one
+ # aka is defined with the break keyword thus does not return
+ readable attr _is_break: Bool
+
+ # Is the closure optional?
+ # ie is there a default definition
+ readable attr _is_optional: Bool
+
+ # Adapt the signature to a different receiver
+ meth adaptation_to(r: MMType): MMClosure
+ do
+ return new MMClosure(_signature.adaptation_to(r), _is_break, _is_optional)
+ end
+
+ init(s: MMSignature, is_break: Bool, is_optional: Bool)
+ do
+ _signature = s
+ _is_break = is_break
+ _is_optional = is_optional
+ end
+
+ meth not_for_self: MMClosure
+ do
+ var sig = _signature.not_for_self
+ if sig != _signature then
+ return new MMClosure(sig, _is_break, _is_optional)
+ else
+ return self
+ end
+ end
+
+ meth <(c: MMClosure): Bool
+ do
+ if c.is_optional and not is_optional then return false
+ if not c.is_break and is_break then return false
+ return c.signature < signature
+ end
+end
+
# Inheritance relation between two types
abstract class MMAncestor
# The inherited type
- readable writable attr _stype: MMType
+ readable writable attr _stype: MMType = null
# The inheriter (heir) type
- readable writable attr _inheriter: MMType
+ readable writable attr _inheriter: MMType = null
meth is_reffinement: Bool do
return stype.module != stype.module
# The local class that self direclty or indirectly refers to
meth local_class: MMLocalClass is abstract
+ # Is the type a valid one
+ # For instance, circular dependency on formal types is invalid
+ meth is_valid: Bool do return true
+
# Is self a valid subtype of t
meth <(t : MMType): Bool is abstract
# Adapt self to another local class context
# Useful for genericity
+ # 'c' Must be a super-class of self
+ # Example:
+ # class A[E]
+ # class B[F] special A[F]
+ # class C[G] special B[String]
+ # class D special C[Float]
+ # 'A[Int]'.upcast_for('A') -> 'A[Int]'
+ # 'A[Int]'.upcast_for('B') -> abort
+ # 'B[Int]'.upcast_for('B') -> 'B[Int]'
+ # 'B[Int]'.upcast_for('A') -> 'A[Int]'
+ # 'B[Int]'.upcast_for('C') -> abort
+ # 'C[Int]'.upcast_for('C') -> 'C[Int]'
+ # 'C[Int]'.upcast_for('B') -> 'B[String]'
+ # 'C[Int]'.upcast_for('A') -> 'A[String]'
+ # 'D'.upcast_for('D') -> 'D'
+ # 'D'.upcast_for('C') -> 'C[Float]'
+ # 'D'.upcast_for('B') -> 'C[String]'
+ # 'D'.upcast_for('A') -> 'A[String]'
meth upcast_for(c: MMLocalClass): MMType is abstract
# Return a type approximation if the reveiver is not self
# Useful for virtual types
meth not_for_self: MMType do return self
+
+ # The nullable version of self (if needed)
+ attr _as_nullable_cache: MMType = null
+
+ # IS the type can accept null?
+ meth is_nullable: Bool do return false
+
+ # Return the nullable version of the type
+ # Noop if already nullable
+ meth as_nullable: MMType do
+ var cache = _as_nullable_cache
+ if cache != null then return cache
+ var res = new MMNullableType(self)
+ _as_nullable_cache = res
+ return res
+ end
+
+ # Return the not null version of the type
+ # Noop if already not null
+ meth as_notnull: MMType do return self
+end
+
+class MMNullableType
+special MMType
+ attr _base_type: MMType
+ redef meth is_nullable: Bool do return true
+ redef meth as_notnull do return _base_type
+ redef meth as_nullable do return self
+ init(t: MMType) do _base_type = t
+
+ redef meth module do return _base_type.module
+
+ redef meth local_class do return _base_type.local_class
+
+ redef meth <(t)
+ do
+ return t isa MMNullableType and _base_type < t.as_notnull
+ end
+
+ redef meth to_s
+ do
+ return "nullable {_base_type}"
+ end
+
+ redef meth is_supertype(t)
+ do
+ return _base_type.is_supertype(t)
+ end
+
+ redef meth for_module(mod)
+ do
+ return _base_type.for_module(mod).as_nullable
+ end
+
+ redef meth adapt_to(recv)
+ do
+ return _base_type.adapt_to(recv).as_nullable
+ end
+
+ redef meth upcast_for(c)
+ do
+ return _base_type.upcast_for(c)
+ end
+
+ redef meth not_for_self
+ do
+ return _base_type.not_for_self.as_nullable
+ end
end
class MMTypeClass
redef meth adapt_to(recv) do return self
- redef init(c: MMLocalClass)
+ init(c: MMLocalClass)
do
super(c)
end
# The type of null
class MMTypeNone
special MMType
- redef readable attr _module: MMModule
- redef meth <(t) do return true
- redef meth is_supertype(t) do return false
- redef meth local_class do abort
- redef meth upcast_for(c) do return self
+ redef readable attr _module: MMModule
+ redef meth is_nullable: Bool do return true
+ redef meth <(t) do return t isa MMTypeNone or t isa MMNullableType
+ redef meth to_s do return "null"
+ redef meth is_supertype(t) do return false
+ redef meth local_class do abort
+ redef meth upcast_for(c) do abort
+ redef meth as_nullable do return self
+ redef meth as_notnull do abort
private init(m: MMModule) do _module = m
end
nitlanguage / nit.git / blobdiff