Introduce named concept for types.

libsolidity/ast/Types.cpp

@@ -3029,6 +3029,17 @@ unsigned FunctionType::storageBytes() const
 		solAssert(false, "Storage size of non-storable function type requested.");
 }
 
+bool FunctionType::nameable() const
+{
+	return
+		(m_kind == Kind::Internal || m_kind == Kind::External) &&
+		!m_bound &&
+		!m_arbitraryParameters &&
+		!m_gasSet &&
+		!m_valueSet &&
+		!m_saltSet;
+}
+
 vector<tuple<string, TypePointer>> FunctionType::makeStackItems() const
 {
 	vector<tuple<string, TypePointer>> slots;

libsolidity/ast/Types.h

@@ -263,6 +263,10 @@ public:
 	/// Returns true if the type can be stored as a value (as opposed to a reference) on the stack,
 	/// i.e. it behaves differently in lvalue context and in value context.
 	virtual bool isValueType() const { return false; }
+	/// @returns true if this type can be used for variables. It returns false for
+	/// types like magic types, literals and function types with a kind that is not
+	/// internal or external.
+	virtual bool nameable() const { return false; }
 	/// @returns a list of named and typed stack items that determine the layout of this type on the stack.
 	/// A stack item either has an empty name and type ``nullptr`` referring to a single stack slot, or
 	/// has a non-empty name and a valid type referring to the stack layout of that type.
@@ -402,6 +406,7 @@ public:
 	unsigned storageBytes() const override { return 160 / 8; }
 	bool leftAligned() const override { return false; }
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	MemberList::MemberMap nativeMembers(ContractDefinition const*) const override;
 
@@ -446,6 +451,7 @@ public:
 	unsigned storageBytes() const override { return m_bits / 8; }
 	bool leftAligned() const override { return false; }
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	std::string toString(bool _short) const override;
 
@@ -492,6 +498,7 @@ public:
 	unsigned storageBytes() const override { return m_totalBits / 8; }
 	bool leftAligned() const override { return false; }
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	std::string toString(bool _short) const override;
 
@@ -639,6 +646,7 @@ public:
 	unsigned storageBytes() const override { return m_bytes; }
 	bool leftAligned() const override { return true; }
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	std::string toString(bool) const override { return "bytes" + util::toString(m_bytes); }
 	MemberList::MemberMap nativeMembers(ContractDefinition const*) const override;
@@ -666,6 +674,7 @@ public:
 	unsigned storageBytes() const override { return 1; }
 	bool leftAligned() const override { return false; }
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	std::string toString(bool) const override { return "bool"; }
 	u256 literalValue(Literal const* _literal) const override;
@@ -773,6 +782,7 @@ public:
 	bool isDynamicallyEncoded() const override;
 	u256 storageSize() const override;
 	bool canLiveOutsideStorage() const override { return m_baseType->canLiveOutsideStorage(); }
+	bool nameable() const override { return true; }
 	std::string toString(bool _short) const override;
 	std::string canonicalName() const override;
 	std::string signatureInExternalFunction(bool _structsByName) const override;
@@ -875,6 +885,7 @@ public:
 	bool leftAligned() const override { solAssert(!isSuper(), ""); return false; }
 	bool canLiveOutsideStorage() const override { return !isSuper(); }
 	bool isValueType() const override { return !isSuper(); }
+	bool nameable() const override { return !isSuper(); }
 	std::string toString(bool _short) const override;
 	std::string canonicalName() const override;
 
@@ -935,6 +946,7 @@ public:
 	u256 memoryDataSize() const override;
 	u256 storageSize() const override;
 	bool canLiveOutsideStorage() const override { return true; }
+	bool nameable() const override { return true; }
 	std::string toString(bool _short) const override;
 
 	MemberList::MemberMap nativeMembers(ContractDefinition const* _currentScope) const override;
@@ -997,6 +1009,7 @@ public:
 	std::string toString(bool _short) const override;
 	std::string canonicalName() const override;
 	bool isValueType() const override { return true; }
+	bool nameable() const override { return true; }
 
 	BoolResult isExplicitlyConvertibleTo(Type const& _convertTo) const override;
 	TypePointer encodingType() const override;
@@ -1202,6 +1215,7 @@ public:
 	bool leftAligned() const override;
 	unsigned storageBytes() const override;
 	bool isValueType() const override { return true; }
+	bool nameable() const override;
 	bool canLiveOutsideStorage() const override { return m_kind == Kind::Internal || m_kind == Kind::External; }
 	bool hasSimpleZeroValueInMemory() const override { return false; }
 	MemberList::MemberMap nativeMembers(ContractDefinition const* _currentScope) const override;
@@ -1339,6 +1353,7 @@ public:
 	bool dataStoredIn(DataLocation _location) const override { return _location == DataLocation::Storage; }
 	/// Cannot be stored in memory, but just in case.
 	bool hasSimpleZeroValueInMemory() const override { solAssert(false, ""); }
+	bool nameable() const override { return true; }
 
 	Type const* keyType() const { return m_keyType; }
 	Type const* valueType() const { return m_valueType; }