A sane flag-package for gophers who just need some CLI flags in Golang projects, not command-structuring frameworks for space ships. If you waved a white flag on the usual whoppers, whiteflag is here to assist.
- simply provides
FlagPresent()to check for specified flags, andGetBool|Int|String()to access their values (these functions can be utilized directly without further setup of each flag) - allows you to distinguish between absent and zero-valued flags
-h/--helpprints basic generated Usage/Help text (see examples)- Default values for flags can be specified
- Required flags can be achieved implicitly (see examples)
Please have a look at the comprehensive example source file.
The following snippet would print "gopher" when called with -p gopher.
package main
import wf "github.com/danielb42/whiteflag"
func main() {
if wf.FlagPresent("p") {
println(wf.GetString("p"))
}
}The next snippet will print the sum of two integers given through -x and -y. For y we specify a default value. Let's also associate long flags to the short flags so we could equivalently run the snippet with --first and --second. Aliasing flags makes them known to the Usage/Help text generation.
package main
import wf "github.com/danielb42/whiteflag"
func main() {
wf.Alias("x", "first", "The first number.")
wf.Alias("y", "second", "The second number.")
wf.SetIntDefault("y", 42)
// we don't do a FlagPresent() check on x und y before Get'ting them so
// the program will exit if x is not specified, thus making x 'required'.
// For a missing y flag, the default value of 42 would be used.
x := wf.GetInt("x")
y := wf.GetInt("y")
sum := x + y
println("sum of x and y:", sum)
}For the snippet above the following Usage/Help text would be available through -h/--help:
Usage: ./example <flags>
Flags:
-x --first The first number.
-y --second The second number.MIT