expvar: add Func for functions that return values that are JSON marshalable.
Remove {Float,Int,String}Func, which are now redundant.
Fixes #1684.
R=rsc, r, r2
CC=golang-dev
https://golang.org/cl/4410041
diff --git a/src/pkg/expvar/expvar.go b/src/pkg/expvar/expvar.go
index ed6cff7..7736aea 100644
--- a/src/pkg/expvar/expvar.go
+++ b/src/pkg/expvar/expvar.go
@@ -180,23 +180,14 @@
func (v *String) Set(value string) { v.s = value }
-// IntFunc wraps a func() int64 to create a value that satisfies the Var interface.
-// The function will be called each time the Var is evaluated.
-type IntFunc func() int64
+// Func implements Var by calling the function
+// and formatting the returned value using JSON.
+type Func func() interface{}
-func (v IntFunc) String() string { return strconv.Itoa64(v()) }
-
-// FloatFunc wraps a func() float64 to create a value that satisfies the Var interface.
-// The function will be called each time the Var is evaluated.
-type FloatFunc func() float64
-
-func (v FloatFunc) String() string { return strconv.Ftoa64(v(), 'g', -1) }
-
-// StringFunc wraps a func() string to create value that satisfies the Var interface.
-// The function will be called each time the Var is evaluated.
-type StringFunc func() string
-
-func (f StringFunc) String() string { return strconv.Quote(f()) }
+func (f Func) String() string {
+ v, _ := json.Marshal(f())
+ return string(v)
+}
// All published variables.
@@ -282,18 +273,16 @@
fmt.Fprintf(w, "\n}\n")
}
-func memstats() string {
- b, _ := json.MarshalIndent(&runtime.MemStats, "", "\t")
- return string(b)
+func cmdline() interface{} {
+ return os.Args
}
-func cmdline() string {
- b, _ := json.Marshal(os.Args)
- return string(b)
+func memstats() interface{} {
+ return runtime.MemStats
}
func init() {
http.Handle("/debug/vars", http.HandlerFunc(expvarHandler))
- Publish("cmdline", StringFunc(cmdline))
- Publish("memstats", StringFunc(memstats))
+ Publish("cmdline", Func(cmdline))
+ Publish("memstats", Func(memstats))
}
