/// <summary> Returns the element type of any class implementing <see cref="IEnumerable{T}" /> interface. Returns null when it is not found. </summary>
public static TypeReference GetElementTypeFromIEnumerable(this SpecializedType collectionType, MetadataContext cx, bool allowIEnumerator, out bool?isGeneric)
{
bool foundNonGenericIEnumerable = false;
foreach (var baseType in cx.GetBaseTypes(collectionType))
{
if (baseType.Type == TypeSignature.IEnumerableOfT || (allowIEnumerator && baseType.Type == TypeSignature.IEnumeratorOfT))
{
isGeneric = true;
return(Assert.Single(baseType.TypeArguments));
}
if (baseType.Type == TypeSignature.IEnumerable || (allowIEnumerator && baseType.Type == TypeSignature.IEnumerator))
{
foundNonGenericIEnumerable = true;
}
}
// System.Collections.IEnumerable found in type hierarchy -> Object is element type.
if (foundNonGenericIEnumerable)
{
isGeneric = false;
return(TypeSignature.Object);
}
isGeneric = null;
return(null);
}
/// <summary>
/// Gets whether this type definition is derived from the base type definition.
/// </summary>
public static bool IsDerivedFrom(this SpecializedType type, SpecializedType baseType, MetadataContext cx)
{
if (type == null)
{
throw new ArgumentNullException("type");
}
if (baseType == null)
{
return(false);
}
return(cx.GetBaseTypes(type).Contains(baseType));
}
/// <summary>
/// Returns all declaring types of this type.
/// The output is ordered so that inner types occur before outer types.
/// </summary>
public static IEnumerable <SpecializedType> GetDeclaringTypes(this SpecializedType type)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
while (type is object)
{
yield return(type);
type = type.DeclaringType();
}
}
/// <summary>
/// Gets the invoke method for a delegate type.
/// </summary>
/// <remarks>
/// Returns null if the type is not a delegate type; or if the invoke method could not be found.
/// </remarks>
public static MethodReference GetDelegateInvokeMethod(this SpecializedType @delegate, MetadataContext cx)
{
if (@delegate == null)
{
throw new ArgumentNullException("type");
}
if (@delegate.Type.Kind == "delegate")
{
return(cx.GetMemberMethods(@delegate).FirstOrDefault(m => m.Name() == "Invoke"));
}
else
{
return(null);
}
}
static partial void ValidateObjectExtension(ref CoreLib.ValidationErrorsBuilder e, SpecializedType t)
{
if (t.Type is null)
{
return;
}
var expectedCount = t.Type.TotalParameterCount();
if (expectedCount != t.TypeArguments.Length)
{
e.Add(ValidationErrors.Create($"Type {t.Type} expected {expectedCount} parameters, got [{string.Join(", ", t.TypeArguments)}]"));
}
}
public static TypeSignature UnwrapSignature(SpecializedType st) => st.TypeArguments.Length == 0 ? st.Type : throw new NotSupportedException($"Generic type is not supported in this context.");
/// <summary>
/// Converts a delegate to a matching function type.
/// </summary>
/// <remarks>
/// Returns null if the type is not a delegate type; or if the invoke method could not be found.
/// </remarks>
public static FunctionType DelegateToFunction(this SpecializedType @delegate, MetadataContext cx)
{
var invoke = @delegate.GetDelegateInvokeMethod(cx);
return(invoke?.ToFunctionType());
}