Float64SliceFlag.ValueFromContext() as convenient accessor

flag_float64_slice.go

@@ -175,6 +175,11 @@ func (f *Float64SliceFlag) Apply(set *flag.FlagSet) error {
 	return nil
 }
 
+// ValueFromContext returns the flag’s value in the given Context.
+func (f *Float64SliceFlag) ValueFromContext(ctx *Context) []float64 {
+	return ctx.Float64Slice(f.Name)
+}
+
 // Float64Slice looks up the value of a local Float64SliceFlag, returns
 // nil if not found
 func (c *Context) Float64Slice(name string) []float64 {

flag_test.go

@@ -1117,6 +1117,14 @@ func TestFloat64SliceFlagWithEnvVarHelpOutput(t *testing.T) {
 	}
 }
 
+func TestFloat64SliceFlagValueFromContext(t *testing.T) {
+	set := flag.NewFlagSet("test", 0)
+	set.Var(NewFloat64Slice(1.23, 4.56), "myflag", "doc")
+	ctx := NewContext(nil, set, nil)
+	f := &Float64SliceFlag{Name: "myflag"}
+	expect(t, f.ValueFromContext(ctx), []float64{1.23, 4.56})
+}
+
 var genericFlagTests = []struct {
 	name     string
 	value    Generic