go/test/typeparam/sum.go
Matthew Dempsky 5355753009 [dev.typeparams] test/typeparam: gofmt -w
We don't usually reformat the test directory, but all of the files in
test/typeparam are syntactically valid. I suspect the misformattings
here are because developers aren't re-installing gofmt with
-tags=typeparams, not intentionally exercising non-standard
formatting.

Change-Id: I3767d480434c19225568f3c7d656dc8589197183
Reviewed-on: https://go-review.googlesource.com/c/go/+/338093
Trust: Matthew Dempsky <mdempsky@google.com>
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2021-07-28 21:40:40 +00:00

50 lines
937 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{ 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))
}
}