Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

92 lines (74 sloc) 3.508 kb
/* NSC -- new Scala compiler
* Copyright 2005-2013 LAMP/EPFL
* @author Paul Phillips
*/
package scala.tools
package cmd
import nsc.Properties.envOrElse
import Spec.Info
/** Machinery for what amounts to a command line specification DSL.
* It is designed so the same specification trait can be used for
* two different purposes: generating a singleton specification object
* (trait Reference) and providing well typed vals for every configurable
* option in response to any given set of arguments (trait Instance).
*/
object Opt {
trait Error {
self: Implicit =>
protected def fail(msg: String) = runAndExit(println(programInfo.runner + ": " + msg))
protected def failOption(arg: String, why: String) = fail("%s: '%s' is %s".format(opt, arg, why))
}
trait Implicit {
def name: String
def programInfo: Info
protected def opt = toOpt(name)
def --? : Boolean // --opt is set
def --> (body: => Unit): Unit // if --opt is set, execute body
def --| : Option[String] // --opt <arg: String> is optional, result is Option[String]
def --^[T: FromString] : Option[T] // --opt <arg: T> is optional, result is Option[T]
def optMap[T](f: String => T) = --| map f
/** Names.
*/
def defaultTo[T: FromString](default: T): T
def defaultToEnv(envVar: String): String
def choiceOf[T: FromString](choices: T*): Option[T]
def expandTo(args: String*): Unit
/** Help.
*/
def /(descr: String): String // --opt has help description 'descr'
}
class Reference(val programInfo: Info, val options: Reference.Accumulators, val name: String) extends Implicit {
import options._
def --? = { addUnary(opt) ; false }
def --> (body: => Unit) = { addUnary(opt) }
def --| = { addBinary(opt) ; None }
def --^[T: FromString] = { addBinary(opt) ; None }
def defaultTo[T: FromString](default: T) = { addBinary(opt) ; addHelpDefault(() => default.toString) ; default }
def defaultToEnv(envVar: String) = { addBinary(opt) ; addHelpEnvDefault(envVar) ; "" }
def choiceOf[T: FromString](choices: T*) = { addBinary(opt) ; None }
def expandTo(args: String*) = { addExpand(name, args.toList) ; addHelpAlias(() => args mkString " ") }
def /(descr: String) = returning(name)(_ => addHelp(() => helpFormatStr.format(opt, descr)))
}
class Instance(val programInfo: Info, val parsed: CommandLine, val name: String) extends Implicit with Error {
def --? = parsed isSet opt
def --> (body: => Unit) = if (parsed isSet opt) body
def --| = parsed get opt
def --^[T: FromString] = {
val fs = implicitly[FromString[T]]
--| map { arg =>
if (fs isDefinedAt arg) fs(arg)
else failOption(arg, "not a " + fs.targetString)
}
}
def defaultTo[T: FromString](default: T) = --^[T] getOrElse default
def defaultToEnv(envVar: String) = --| getOrElse envOrElse(envVar, "")
def expandTo(args: String*) = ()
def choiceOf[T: FromString](choices: T*) = {
--^[T] map { arg =>
if (choices contains arg) arg
else failOption(arg.toString, "not a valid choice from " + choices)
}
}
def /(descr: String) = name
}
}
Jump to Line
Something went wrong with that request. Please try again.