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// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package p
type myInt int
// Parameterized type declarations
type T1[P any] P
type T2[P any] struct {
f P
g int // int should still be in scope chain
}
type List[P any] []P
// Alias type declarations cannot have type parameters. Syntax error.
type A1[P any] = /* ERROR cannot be alias */ P
// But an alias may refer to a generic, uninstantiated type.
type A2 = List
var _ A2[int]
var _ A2 /* ERROR without instantiation */
type A3 = List[int]
var _ A3
// Parameterized type instantiations
var x int
type _ x /* ERROR not a type */ [int]
type _ int /* ERROR not a generic type */ [] // ERROR expected type argument list
type _ myInt /* ERROR not a generic type */ [] // ERROR expected type argument list
// TODO(gri) better error messages
type _ T1[] // ERROR expected type argument list
type _ T1[x /* ERROR not a type */ ]
type _ T1 /* ERROR got 2 arguments but 1 type parameters */ [int, float32]
var _ T2[int] = T2[int]{}
var _ List[int] = []int{1, 2, 3}
var _ List[[]int] = [][]int{{1, 2, 3}}
var _ List[List[List[int]]]
// Parameterized types containing parameterized types
type T3[P any] List[P]
var _ T3[int] = T3[int](List[int]{1, 2, 3})
// Self-recursive generic types are not permitted
type self1[P any] self1 /* ERROR illegal cycle */ [P]
type self2[P any] *self2[P] // this is ok
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