Add hello world example and add more options

command.go

@@ -2,6 +2,9 @@ package cmd
 
 import "go.fifitido.net/cmd/flags"
 
+type RunFunc func(args []string)
+type RunErrFunc func(args []string) error
+
 type Command struct {
 	Name             string
 	ShortDescription string
@@ -10,8 +13,8 @@ type Command struct {
 	Arguments        []*Argument
 	Flags            []flags.Flag
 	Subcommands      []*Command
-	Run              func(args []string)
+	Run              RunFunc
-	RunE             func(args []string) error
+	RunE             RunErrFunc
 	isRoot           bool
 }
 

examples/hello-world/cmd/main.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"go.fifitido.net/cmd"
+)
+
+var root = cmd.NewRoot(
+	cmd.WithShortDescription("Example command"),
+	cmd.WithLongDescription(`An example command to show how to use go.fifitido.net/cmd
+
+this example is just a simple hello world program to show
+the basics of the library.`),
+	cmd.WithArgument("name", false),
+	cmd.WithRunFunc(func(args []string) {
+		if len(args) == 0 {
+			fmt.Println("Hello World!")
+		} else {
+			fmt.Printf("Hello %s!\n", args[0])
+		}
+	}),
+)
+
+func main() {
+	root.Execute(os.Args)
+}

examples/hello-world/go.mod

@@ -0,0 +1,5 @@
+module go.fifitido.net/cmd/examples/hello-world
+
+go 1.21.3
+
+require go.fifitido.net/cmd v0.0.0-20231110043437-c32ce2efcd5f

examples/hello-world/go.sum

@@ -0,0 +1,2 @@
+go.fifitido.net/cmd v0.0.0-20231110043437-c32ce2efcd5f h1:v+sjO+t6cGEtDhStOnuypYBrkOMO4suiDVxL93rOUCs=
+go.fifitido.net/cmd v0.0.0-20231110043437-c32ce2efcd5f/go.mod h1:8SaDxCG1m6WwShUlZApSbNleCvV7oTfqZIyYu4aAqO0=

option.go

@@ -4,6 +4,18 @@ import "go.fifitido.net/cmd/flags"
 
 type Option func(*Command)
 
+func WithShortDescription(s string) Option {
+	return func(c *Command) {
+		c.ShortDescription = s
+	}
+}
+
+func WithLongDescription(s string) Option {
+	return func(c *Command) {
+		c.LongDescription = s
+	}
+}
+
 func WithArgument(name string, required bool) Option {
 	return func(c *Command) {
 		c.Arguments = append(c.Arguments, &Argument{name, required})
@@ -39,3 +51,15 @@ func WithSubcommands(ss []*Command) Option {
 		c.Subcommands = append(c.Subcommands, ss...)
 	}
 }
+
+func WithRunFunc(r RunFunc) Option {
+	return func(c *Command) {
+		c.Run = r
+	}
+}
+
+func WithRunErrFunc(r RunErrFunc) Option {
+	return func(c *Command) {
+		c.RunE = r
+	}
+}