args.go

package cli

import (
	"fmt"
	"reflect"
)

// BoolArg describes a boolean argument
type BoolArg struct {
	BoolParam

	// The argument name as will be shown in help messages
	Name string
	// The argument description as will be shown in help messages
	Desc string
	// A space separated list of environment variables names to be used to initialize this argument
	EnvVar string
	// The argument's inital value
	Value bool
	// A boolean to display or not the current value of the argument in the help message
	HideValue bool
}

// StringArg describes a string argument
type StringArg struct {
	StringParam

	// The argument name as will be shown in help messages
	Name string
	// The argument description as will be shown in help messages
	Desc string
	// A space separated list of environment variables names to be used to initialize this argument
	EnvVar string
	// The argument's inital value
	Value string
	// A boolean to display or not the current value of the argument in the help message
	HideValue bool
}

// IntArg describes an int argument
type IntArg struct {
	IntParam

	// The argument name as will be shown in help messages
	Name string
	// The argument description as will be shown in help messages
	Desc string
	// A space separated list of environment variables names to be used to initialize this argument
	EnvVar string
	// The argument's inital value
	Value int
	// A boolean to display or not the current value of the argument in the help message
	HideValue bool
}

// StringsArg describes a string slice argument
type StringsArg struct {
	StringsParam

	// The argument name as will be shown in help messages
	Name string
	// The argument description as will be shown in help messages
	Desc string
	// A space separated list of environment variables names to be used to initialize this argument.
	// The env variable should contain a comma separated list of values
	EnvVar string
	// The argument's inital value
	Value []string
	// A boolean to display or not the current value of the argument in the help message
	HideValue bool
}

// IntsArg describes an int slice argument
type IntsArg struct {
	IntsParam

	// The argument name as will be shown in help messages
	Name string
	// The argument description as will be shown in help messages
	Desc string
	// A space separated list of environment variables names to be used to initialize this argument.
	// The env variable should contain a comma separated list of values
	EnvVar string
	// The argument's inital value
	Value []int
	// A boolean to display or not the current value of the argument in the help message
	HideValue bool
}

/*
BoolArg defines a boolean argument on the command c named `name`, with an initial value of `value` and a description of `desc` which will be used in help messages.

The result should be stored in a variable (a pointer to a bool) which will be populated when the app is run and the call arguments get parsed
*/
func (c *Cmd) BoolArg(name string, value bool, desc string) *bool {
	return c.mkArg(arg{name: name, desc: desc}, value).(*bool)
}

/*
StringArg defines a string argument on the command c named `name`, with an initial value of `value` and a description of `desc` which will be used in help messages.

The result should be stored in a variable (a pointer to a string) which will be populated when the app is run and the call arguments get parsed
*/
func (c *Cmd) StringArg(name string, value string, desc string) *string {
	return c.mkArg(arg{name: name, desc: desc}, value).(*string)
}

/*
IntArg defines an int argument on the command c named `name`, with an initial value of `value` and a description of `desc` which will be used in help messages.

The result should be stored in a variable (a pointer to an int) which will be populated when the app is run and the call arguments get parsed
*/
func (c *Cmd) IntArg(name string, value int, desc string) *int {
	return c.mkArg(arg{name: name, desc: desc}, value).(*int)
}

/*
StringsArg defines a string slice argument on the command c named `name`, with an initial value of `value` and a description of `desc` which will be used in help messages.

The result should be stored in a variable (a pointer to a string slice) which will be populated when the app is run and the call arguments get parsed
*/
func (c *Cmd) StringsArg(name string, value []string, desc string) *[]string {
	return c.mkArg(arg{name: name, desc: desc}, value).(*[]string)
}

/*
IntsArg defines an int slice argument on the command c named `name`, with an initial value of `value` and a description of `desc` which will be used in help messages.

The result should be stored in a variable (a pointer to an int slice) which will be populated when the app is run and the call arguments get parsed
*/
func (c *Cmd) IntsArg(name string, value []int, desc string) *[]int {
	return c.mkArg(arg{name: name, desc: desc}, value).(*[]int)
}

type arg struct {
	name          string
	desc          string
	envVar        string
	helpFormatter func(interface{}) string
	value         reflect.Value
	hideValue     bool
}

func (a *arg) String() string {
	return fmt.Sprintf("ARG(%s)", a.name)
}

func (a *arg) get() interface{} {
	return a.value.Elem().Interface()
}

func (a *arg) set(s string) error {
	return vset(a.value, s)
}

func (c *Cmd) mkArg(arg arg, defaultvalue interface{}) interface{} {
	value := reflect.ValueOf(defaultvalue)
	res := reflect.New(value.Type())

	arg.helpFormatter = formatterFor(value.Type())

	vinit(res, arg.envVar, defaultvalue)

	arg.value = res

	c.args = append(c.args, &arg)
	c.argsIdx[arg.name] = &arg

	return res.Interface()
}