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// Copyright 2022 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 main
import (
"fmt"
"go/ast"
"go/parser"
"go/token"
"go/types"
"log"
"golang.org/x/exp/typeparams"
)
const src = `
//!+input
package complex
type A interface{ ~string|~[]byte }
type B interface{ int|string }
type C interface { ~string|~int }
type D interface{ A|B; C }
//!-input
`
// !+print
func PrintNormalTerms(pkg *types.Package) error {
D := pkg.Scope().Lookup("D").Type()
terms, err := typeparams.NormalTerms(D)
if err != nil {
return err
}
for i, term := range terms {
if i > 0 {
fmt.Print("|")
}
fmt.Print(term)
}
fmt.Println()
return nil
}
//!-print
/*
//!+output
~string|int
//!-output
*/
func main() {
fset := token.NewFileSet()
f, err := parser.ParseFile(fset, "p.go", src, 0)
if err != nil {
log.Fatal(err)
}
conf := types.Config{}
pkg, err := conf.Check("typesets", fset, []*ast.File{f}, nil)
if err != nil {
log.Fatal(err)
}
if err := PrintNormalTerms(pkg); err != nil {
log.Fatal(err)
}
}
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