On Thursday, July 4, 2019 at 3:28:01 AM UTC+2, Ian Lance Taylor wrote:
>
> On Wed, Jul 3, 2019 at 6:19 PM Gert <gert....@gmail.com <javascript:>>
> wrote:
> >
> > On Thursday, July 4, 2019 at 2:52:42 AM UTC+2, Ian Lance Taylor wrote:
> >>
> >> On Wed, Jul 3, 2019 at 4:39 PM Gert <gert....@gmail.com> wrote:
> >> >
> >> > On Thursday, July 4, 2019 at 12:39:34 AM UTC+2, Ian Lance Taylor
> wrote:
> >> >>
> >> >> On Wed, Jul 3, 2019 at 3:30 PM Gert <gert....@gmail.com> wrote:
> >> >> >
> >> >> > I changed /usr/local/go/src/builtin/builtin.go
> >> >> >
> >> >> > type error interface {
> >> >> > Error() string
> >> >> > Unwrap() wrapper.Wrapper
> >> >> > }
> >> >> >
> >> >> > But after compiling go successfully with ./all.bash it seems type
> error is stil
> >> >> >
> >> >> > type error interface {
> >> >> > Error() string
> >> >> > }
> >> >>
> >> >> The type "error" is implemented directly in the Go compiler. The
> code
> >> >> in builtin/builtin.go only exists for documentation purposes. If
> you
> >> >> want to change error, you'll need to change the compiler.
> >> >
> >> >
> >> > Ok thx trying to dig my way in /usr/local/go/src/go but grepping for
> error interface doesn't give me a clue where I can find the predefined
> error interface :( do you perhaps have a path of a filename for me please
> where it get defined?
> >>
> >> It's created by makeErrorInterface in
> >> cmd/compile/internal/gc/universe.go. But I have no idea what the
> >> consequences of changing that function would be. I would not be
> >> surprised if other code in the compiler implicitly assumes the current
> >> definition.
> >>
> >> Ian
> >
> >
> > Thanks before I going to shoot myself in the foot let start by making a
> new build in wrapper interface first in that file
> >
> > func makeWrapperInterface() *types.Type {
> > field := types.NewField()
> > field.Type = types.Types[TSTRING]
> > f := functypefield(fakeRecvField(), nil, []*types.Field{field})
> >
> > field = types.NewField()
> > field.Sym = lookup("Wrapper")
> > field.Type = f
> >
> > t := types.New(TINTER)
> > t.SetInterface([]*types.Field{field})
> > return t
> > }
> >
> > So basically this should generate a new build in
> >
> > type wrapper interface {
> > Unwrap() wrapper
> > }
> >
> > Because referencing to a wrapper.Wrapper pretty sure that's already out
> of the question :)
> > The lookup function gives me a hint that there might be some definition
> files that describe the interface in plain text? If true do you know where
> I can find does files specifically the error interface definition file?
>
> As far as I know there is no definition file that defines the interface in
> text.
>
> As you can see by looking at the source of the lookup function, all it
> does is look up a symbol in the local package's symbol table, and
> create the symbol if it does not exist.
>
> I encourage you to pursue this approach if you are interested in it,
> but in order to do so you are going to have to learn to read and
> understand the compiler code yourself, or find someone to work with
> who has the time to go through it in the detail you need.
>
> Ian
>
Ok thanks, this my best try so far to make it happen, hopefully good enough
to find out if it's worth it to go for a more general built-in wrapper
interface for all types instead of a error wrapper only.
https://go-review.googlesource.com/c/go/+/184818/5
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/a90e743b-5212-4470-a06d-80dbe42169da%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
