go/test/typeparam/map.go
Dan Scales c0aa7bd760 [dev.typeparams] cmd/compile: small fixes for stenciling
- Create the stencil name using targ.Type.String(), which handles cases
   where, for example, a type argument is a pointer to a named type,
   etc. *obj.

 - Set name.Def properly for a new stenciled func (have the symbol point
   back to the associated function node).  Will be required when exporting.

 - Add missing copying of Func field when making copies of Name nodes.
   (On purpose (it seems), Name nodes don't have a copy() function, so
   we have to copy all the needed fields explicitly.)

 - Deal with nil type in subster.node(), which is the type of the return
   value for a function that doesn't return anything.

 - Fix min to match standard want/go form, and add in float tests.  Changed
   Got -> got in bunch of other typeparam tests.

 - Add new tests index.go, settable.go, and smallest.go (similar to
   examples in the type param proposal), some of which need the above
   changes.

Change-Id: I09a72302bc1fd3635a326da92405222afa222e85
Reviewed-on: https://go-review.googlesource.com/c/go/+/291109
Trust: Dan Scales <danscales@google.com>
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2021-02-11 21:46:39 +00:00

40 lines
899 B
Go

// run -gcflags=-G=3
// Copyright 2021 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"
"reflect"
"strconv"
)
// Map calls the function f on every element of the slice s,
// returning a new slice of the results.
func mapper[F, T any](s []F, f func(F) T) []T {
r := make([]T, len(s))
for i, v := range s {
r[i] = f(v)
}
return r
}
func main() {
got := mapper([]int{1, 2, 3}, strconv.Itoa)
want := []string{"1", "2", "3"}
if !reflect.DeepEqual(got, want) {
panic(fmt.Sprintf("got %s, want %s", got, want))
}
fgot := mapper([]float64{2.5, 2.3, 3.5}, func(f float64) string {
return strconv.FormatFloat(f, 'f', -1, 64)
})
fwant := []string{"2.5", "2.3", "3.5"}
if !reflect.DeepEqual(fgot, fwant) {
panic(fmt.Sprintf("got %s, want %s", fgot, fwant))
}
}