}

	case *Map:
		// Two map types are identical if they have identical key and value types.
		if y, ok := y.(*Map); ok {
			return c.identical(x.key, y.key, p) && c.identical(x.elem, y.elem, p)
		}

	case *Chan:
		// Two channel types are identical if they have identical value types
		// and the same direction.
		if y, ok := y.(*Chan); ok {
			return x.dir == y.dir && c.identical(x.elem, y.elem, p)
		}

	case *Named:

func Identical(t1, t2 *Type) bool {
	return identical(t1, t2, 0, nil)
}

// IdenticalIgnoreTags is like Identical, but it ignores struct tags
// for struct identity.
func IdenticalIgnoreTags(t1, t2 *Type) bool {
	return identical(t1, t2, identIgnoreTags, nil)
}

// IdenticalStrict is like Identical, but matches types exactly, without the
// exception for shapes.
func IdenticalStrict(t1, t2 *Type) bool {

		}

	case *Map:
		// Two map types are identical if they have identical key and value types.
		if y, ok := y.(*Map); ok {
			return c.identical(x.key, y.key, p) && c.identical(x.elem, y.elem, p)
		}

	case *Chan:
		// Two channel types are identical if they have identical value types
		// and the same direction.
		if y, ok := y.(*Chan); ok {
			return x.dir == y.dir && c.identical(x.elem, y.elem, p)
		}

	case *Named:

		return nil // no core type.
	}

	U = terms[0].Type().Underlying()
	var identical int // i in [0,identical) => Identical(U, terms[i].Type().Underlying())
	for identical = 1; identical < len(terms); identical++ {
		if !types.Identical(U, terms[identical].Type().Underlying()) {
			break
		}
	}

	if identical == len(terms) {
		// https://go.dev/ref/spec#Core_types

//
// Contexts serve two purposes:
//  - reduce the duplication of identical instances
//  - short-circuit instantiation cycles
//
// For the latter purpose, we must always have a context during instantiation,
// whether or not it is supplied by the user. For both purposes, it must be the
// case that hashing a pointer-identical type produces consistent results
// (somewhat obviously).
//

	return (*Checker)(nil).implements(nopos, V, T, true, nil)
}

// Identical reports whether x and y are identical types.
// Receivers of [Signature] types are ignored.
//
// Predicates such as [Identical], [Implements], and
// [Satisfies] assume that both operands belong to a
// consistent collection of symbols ([Object] values).
// For example, two [Named] types can be identical only if their
// [Named.Obj] methods return the same [TypeName] symbol.

		t.Error("bad")
	}

	// unaryP is not identical to nullaryP, so we should not get inst when
	// instantiated with identical type arguments.
	if got := ctxt.lookup("", unaryP, []Type{Typ[Int]}); got != nil {
		t.Error("bad")
	}

	// nullaryQ is identical to nullaryP, so we *should* get inst when
	// instantiated with identical type arguments.
	if got := ctxt.lookup("", nullaryQ, []Type{Typ[Int]}); got != inst {

//
// Contexts serve two purposes:
//  - reduce the duplication of identical instances
//  - short-circuit instantiation cycles
//
// For the latter purpose, we must always have a context during instantiation,
// whether or not it is supplied by the user. For both purposes, it must be the
// case that hashing a pointer-identical type produces consistent results
// (somewhat obviously).
//

	return (*Checker)(nil).implements(nopos, V, T, true, nil)
}

// Identical reports whether x and y are identical types.
// Receivers of [Signature] types are ignored.
//
// Predicates such as [Identical], [Implements], and
// [Satisfies] assume that both operands belong to a
// consistent collection of symbols ([Object] values).
// For example, two [Named] types can be identical only if their
// [Named.Obj] methods return the same [TypeName] symbol.

        expect:
        fails("resolveSample")
        failure.assertHasDocumentedCause("Consumable configurations with identical capabilities within a project (other than the default configuration) must have unique attributes, but configuration ':sample1' and [configuration ':sample2'] contain identical attribute sets. " +
            "Consider adding an additional attribute to one of the configurations to disambiguate them.  " +