arg/example_test.go

103 lines
2.6 KiB
Go

package arg
import (
"fmt"
"os"
)
// This example demonstrates basic usage
func Example() {
// These are the args you would pass in on the command line
os.Args = []string{"./example", "--foo=hello", "--bar"}
var args struct {
Foo string
Bar bool
}
MustParse(&args)
fmt.Println(args.Foo, args.Bar)
}
// This example demonstrates arguments that have default values
func Example_defaultValues() {
// These are the args you would pass in on the command line
os.Args = []string{"--help"}
var args struct {
Foo string
Bar bool
}
args.Foo = "default value"
MustParse(&args)
fmt.Println(args.Foo, args.Bar)
}
// This example demonstrates arguments that are required
func Example_requiredArguments() {
// These are the args you would pass in on the command line
os.Args = []string{"--foo=1", "--bar"}
var args struct {
Foo string `arg:"required"`
Bar bool
}
MustParse(&args)
}
// This example demonstrates positional arguments
func Example_positionalArguments() {
// These are the args you would pass in on the command line
os.Args = []string{"./example", "in", "out1", "out2", "out3"}
var args struct {
Input string `arg:"positional"`
Output []string `arg:"positional"`
}
MustParse(&args)
fmt.Println("Input:", args.Input)
fmt.Println("Output:", args.Output)
}
// This example demonstrates arguments that have multiple values
func Example_multipleValues() {
// The args you would pass in on the command line
os.Args = []string{"--help"}
var args struct {
Database string
IDs []int64
}
MustParse(&args)
fmt.Printf("Fetching the following IDs from %s: %q", args.Database, args.IDs)
}
// This eample demonstrates multiple value arguments that can be mixed with
// other arguments.
func Example_multipleMixed() {
os.Args = []string{"./example", "-c", "cmd1", "db1", "-f", "file1", "db2", "-c", "cmd2", "-f", "file2", "-f", "file3", "db3", "-c", "cmd3"}
var args struct {
Commands []string `arg:"-c,separate"`
Files []string `arg:"-f,separate"`
Databases []string `arg:"positional"`
}
MustParse(&args)
fmt.Println("Commands:", args.Commands)
fmt.Println("Files", args.Files)
fmt.Println("Databases", args.Databases)
}
// This example shows the usage string generated by go-arg
func Example_usageString() {
// These are the args you would pass in on the command line
os.Args = []string{"--help"}
var args struct {
Input string `arg:"positional"`
Output []string `arg:"positional"`
Verbose bool `arg:"-v,help:verbosity level"`
Dataset string `arg:"help:dataset to use"`
Optimize int `arg:"-O,help:optimization level"`
}
MustParse(&args)
}