mirror of
https://github.com/golang/go
synced 2024-11-19 01:14:39 -07:00
7a70c382be
reflect.Values may point to tagged objects with
interface type, e.g. x := reflect.ValueOf(new(interface{})).Elem().
We failed to consider this when implementing Elem.
Also, (reflect.Value).Interface() must do one "unboxing"
when it encounters such tagged objects.
i.e., x.Elem().Interface() and x.Interface() are equivalent
in that case.
Also:
- add example of tagged object with interface type.
- untabify (Label).String docstring.
- added tests.
R=crawshaw
CC=golang-dev
https://golang.org/cl/18020044
46 lines
1016 B
Go
46 lines
1016 B
Go
// +build ignore
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package main
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import "reflect"
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type A struct {
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f *int
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g interface{}
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h bool
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}
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var dyn string
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func reflectTypeFieldByName() {
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f, _ := reflect.TypeOf(A{}).FieldByName("f")
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print(f.Type) // @pointsto *int
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g, _ := reflect.TypeOf(A{}).FieldByName("g")
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print(g.Type) // @pointsto interface{}
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print(reflect.Zero(g.Type)) // @pointsto <alloc in reflect.Zero>
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print(reflect.Zero(g.Type)) // @types interface{}
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print(reflect.Zero(g.Type).Interface()) // @pointsto
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print(reflect.Zero(g.Type).Interface()) // @types
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h, _ := reflect.TypeOf(A{}).FieldByName("h")
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print(h.Type) // @pointsto bool
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missing, _ := reflect.TypeOf(A{}).FieldByName("missing")
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print(missing.Type) // @pointsto
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dyn, _ := reflect.TypeOf(A{}).FieldByName(dyn)
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print(dyn.Type) // @pointsto *int | bool | interface{}
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}
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func reflectTypeField() {
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fld := reflect.TypeOf(A{}).Field(0)
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print(fld.Type) // @pointsto *int | bool | interface{}
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}
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func main() {
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reflectTypeFieldByName()
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reflectTypeField()
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}
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