TODO download link
Pure Kotlin implementation of a generic command-line parser.
- Declarative: describe what your commands and parameters are
- Platform-agnostic: core library has no platform-specific dependencies and can be used in any Kotlin project
- Hackable: build extensions on top of it however you like
kotlinx.cli can be used to create user-friendly and flexible command-line interfaces
for Kotlin/JVM, Kotlin/Native, and any other Kotlin console applications.
Program defines what arguments are expected.
kotlinx.cli will figure out how to parse those, reporting errors if the program arguments are invalid,
and also generate help and usage messages as well.
package kotlinx.cli.examples
import kotlinx.cli.*
import kotlin.system.exitProcess
fun main(args: Array<String>) {
// Define command-line interface
val cli = CommandLineInterface("Example1")
val integers by cli.positionalArgumentsList("N ", "Integers", minArgs = 1)
val radix by cli.flagValueArgument("-r", "radix", "Input numbers radix", 10) { it.toInt() }
val sum by cli.flagArgument("--sum", "Print sum")
val max by cli.flagArgument("--max", "Print max")
val min by cli.flagArgument("--min", "Print min")
// Parse arguments or exit
try {
cli.parse(args)
}
catch (e: Exception) {
exitProcess(1)
}
// Do something useful
val ints = integers.map { it.toInt(radix) }
println("Args: ${args.asList()}")
println("Integers: $ints")
if (sum) println("Sum: ${ints.sum()}")
if (max) println("Max: ${ints.max()}")
if (min) println("Min: ${ints.min()}")
}Running this program without arguments produces the following output:
Usage: Example1 [-h] N [-r radix] [--sum] [--max] [--min]
-h, --help Prints help
N Integers
-r radix Input numbers radix
--sum Print sum
--max Print max
--min Print min
Now, do some real work: run it with arguments -r 16 CAFE BABE DEAD BEEF --sum
Args: [-r, 16, CAFE, BABE, DEAD, BEEF, --sum]
Integers: [51966, 47806, 57005, 48879]
Sum: 205656