go/test/typeparam/sum.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

50 lines
945 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"
)
func sum[T interface{ type int, float64 }](vec []T) T {
var sum T
for _, elt := range vec {
sum = sum + elt
}
return sum
}
func abs(f float64) float64 {
if f < 0.0 {
return -f
}
return f
}
func main() {
vec1 := []int{3, 4}
vec2 := []float64{5.8, 9.6}
got := sum[int](vec1)
want := vec1[0] + vec1[1]
if got != want {
panic(fmt.Sprintf("got %d, want %d", got, want))
}
got = sum(vec1)
if want != got {
panic(fmt.Sprintf("got %d, want %d", got, want))
}
fwant := vec2[0] + vec2[1]
fgot := sum[float64](vec2)
if abs(fgot - fwant) > 1e-10 {
panic(fmt.Sprintf("got %f, want %f", fgot, fwant))
}
fgot = sum(vec2)
if abs(fgot - fwant) > 1e-10 {
panic(fmt.Sprintf("got %f, want %f", fgot, fwant))
}
}