Add new FlagSet.Get{Int,String,...} accessor functions

If I declared a bool flag named "hello" I can now call

b, err := f.GetBool("hello")

And b will hold the value of the flag

We can see this is already done in
https://github.com/codegangsta/cli/blob/bcec9b08c7e5564f7512ad7e7b03778fe1923116/context.go
If people use the codegangsta/cli

Other projects have done it themselves using pflags (what inspired this
patch)
https://github.com/GoogleCloudPlatform/kubernetes/blob/cd817aebd848facda29e0befbbd6e31bf22402e6/pkg/kubectl/cmd/util/helpers.go#L176

Lets just do it ourselves...

1 files changed, 21 insertions, 0 deletions

diff --git a/flag.go b/flag.go
index 0070b93..534fce4 100644
--- a/flag.go
+++ b/flag.go
@@ -257,6 +257,27 @@ func (f *FlagSet) lookup(name NormalizedName) *Flag {
 	return f.formal[name]
 }
 
+// func to return a given type for a given flag name
+func (f *FlagSet) getFlagType(name string, ftype string, convFunc func(sval string) (interface{}, error)) (interface{}, error) {
+	flag := f.Lookup(name)
+	if flag == nil {
+		err := fmt.Errorf("flag accessed but not defined: %s\n", name)
+		return nil, err
+	}
+
+	if flag.Value.Type() != ftype {
+		err := fmt.Errorf("trying to get %s value of flag of type %s\n", ftype, flag.Value.Type())
+		return nil, err
+	}
+
+	sval := flag.Value.String()
+	result, err := convFunc(sval)
+	if err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
 // Mark a flag deprecated in your program
 func (f *FlagSet) MarkDeprecated(name string, usageMessage string) error {
 	flag := f.Lookup(name)