content: elaborate on function values
The description was a little bit sparse.
The next slide talks about closures, but since the idea of
function values wasn't clear to all readers, some people got
confused when the next slide defined a function that had
a function as a return value.
Fixes golang/go#4284
Change-Id: Id71f71cafb7c411dbad8306980f7eb1d75aa59e5
Reviewed-on: https://go-review.googlesource.com/15752
Reviewed-by: Andrew Gerrand <adg@golang.org>
diff --git a/content/moretypes.article b/content/moretypes.article
index 1d8f9f8..4b06a39 100644
--- a/content/moretypes.article
+++ b/content/moretypes.article
@@ -239,7 +239,9 @@
* Function values
-Functions are values too.
+Functions are values too. They can be passed around just like other values.
+
+Functions values may be used as function arguments and return values.
.play moretypes/function-values.go
diff --git a/content/moretypes/function-values.go b/content/moretypes/function-values.go
index 7642957..0527d71 100644
--- a/content/moretypes/function-values.go
+++ b/content/moretypes/function-values.go
@@ -7,10 +7,16 @@
"math"
)
+func compute(fn func(float64, float64) float64) float64 {
+ return fn(3, 4)
+}
+
func main() {
hypot := func(x, y float64) float64 {
return math.Sqrt(x*x + y*y)
}
+ fmt.Println(hypot(5, 12))
- fmt.Println(hypot(3, 4))
+ fmt.Println(compute(hypot))
+ fmt.Println(compute(math.Pow))
}
