When comparing symbols internally in the compiler, it is possible to pass the TypeCompareKind which specifies the strictness of the comparison.
In VB there is an option TypeCompareKind.IgnoreCustomModifiersAndArraySizesAndLowerBounds which should allow two types which differ only by the presence of custom modifiers to compare equally.
Consider:
Compilation:
Namespace N
Public Class A(Of T)
Public Function M(t As A(Of T)) As A(Of T)
t.M(t)
Return t
End Function
End Class
End NamespaceTest:
Dim syntaxTree = compilation.SyntaxTrees(0)
Dim root = syntaxTree.GetRoot()
Dim model = compilation.GetSemanticModel(syntaxTree)
Dim aSyntax = CType(root.DescendantNodes().First(Function(sn) sn.Kind() = SyntaxKind.ClassBlock), Syntax.ClassBlockSyntax)
Dim aSymbol = CType(model.GetDeclaredSymbol(aSyntax), NamedTypeSymbol)
Dim modifiers = ImmutableArray.Create(VisualBasicCustomModifier.CreateOptional(compilation.GetSpecialType(SpecialType.System_Object)))
Dim substitutedTypes = ImmutableArray.Create((New TypeWithModifiers(aSymbol.TypeParameters.Single(), modifiers)))
Dim modSymbol = aSymbol.Construct(TypeSubstitution.Create(aSymbol, aSymbol.TypeParameters, substitutedTypes))
Dim method1 = CType(aSymbol.GetMembers("M").Single(), IMethodSymbol) ' A(Of T).M(t AS A(Of T)) As A(Of T)
Dim method2 = CType(modSymbol.GetMembers("M").Single(), IMethodSymbol) ' A(Of T modopt(Object)).M(t AS A(Of T modopt(Object)) AS A(Of T modopt(Object))
method1 and method2 should compare equal when ignoring custom modifiers and not equal by default.
When comparing symbols internally in the compiler, it is possible to pass the
TypeCompareKindwhich specifies the strictness of the comparison.In VB there is an option
TypeCompareKind.IgnoreCustomModifiersAndArraySizesAndLowerBoundswhich should allow two types which differ only by the presence of custom modifiers to compare equally.Consider:
Compilation:
Test:
method1andmethod2should compare equal when ignoring custom modifiers and not equal by default.