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-rw-r--r--vendor/golang.org/x/tools/go/types/typeutil/example_test.go67
1 files changed, 67 insertions, 0 deletions
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/example_test.go b/vendor/golang.org/x/tools/go/types/typeutil/example_test.go
new file mode 100644
index 0000000..86c4d44
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/example_test.go
@@ -0,0 +1,67 @@
+// Copyright 2014 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 typeutil_test
+
+import (
+ "fmt"
+ "go/ast"
+ "go/parser"
+ "go/token"
+ "go/types"
+ "sort"
+
+ "golang.org/x/tools/go/types/typeutil"
+)
+
+func ExampleMap() {
+ const source = `package P
+
+var X []string
+var Y []string
+
+const p, q = 1.0, 2.0
+
+func f(offset int32) (value byte, ok bool)
+func g(rune) (uint8, bool)
+`
+
+ // Parse and type-check the package.
+ fset := token.NewFileSet()
+ f, err := parser.ParseFile(fset, "P.go", source, 0)
+ if err != nil {
+ panic(err)
+ }
+ pkg, err := new(types.Config).Check("P", fset, []*ast.File{f}, nil)
+ if err != nil {
+ panic(err)
+ }
+
+ scope := pkg.Scope()
+
+ // Group names of package-level objects by their type.
+ var namesByType typeutil.Map // value is []string
+ for _, name := range scope.Names() {
+ T := scope.Lookup(name).Type()
+
+ names, _ := namesByType.At(T).([]string)
+ names = append(names, name)
+ namesByType.Set(T, names)
+ }
+
+ // Format, sort, and print the map entries.
+ var lines []string
+ namesByType.Iterate(func(T types.Type, names interface{}) {
+ lines = append(lines, fmt.Sprintf("%s %s", names, T))
+ })
+ sort.Strings(lines)
+ for _, line := range lines {
+ fmt.Println(line)
+ }
+
+ // Output:
+ // [X Y] []string
+ // [f g] func(offset int32) (value byte, ok bool)
+ // [p q] untyped float
+}