Uint64Flag.ValueFromContext() as convenient accessor

flag_test.go

@@ -825,6 +825,14 @@ func TestUint64FlagWithEnvVarHelpOutput(t *testing.T) {
 	}
 }
 
+func TestUint64FlagValueFromContext(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Uint64("myflag", 42, "doc")
+	ctx := NewContext(nil, set, nil)
+	f := &Uint64Flag{Name: "myflag"}
+	expect(t, f.ValueFromContext(ctx), uint64(42))
+}
+
 var durationFlagTests = []struct {
 	name     string
 	expected string

flag_uint64.go

@@ -101,6 +101,11 @@ func (f *Uint64Flag) GetEnvVars() []string {
 	return f.EnvVars
 }
 
+// ValueFromContext returns the flag’s value in the given Context.
+func (f *Uint64Flag) ValueFromContext(ctx *Context) uint64 {
+	return ctx.Uint64(f.Name)
+}
+
 // Uint64 looks up the value of a local Uint64Flag, returns
 // 0 if not found
 func (c *Context) Uint64(name string) uint64 {