/* Title: Pure/library.scala
Author: Makarius
Basic library.
*/
package isabelle
import java.lang.System
import java.awt.Component
import javax.swing.JOptionPane
object Library
{
/* separate */
def separate[A](s: A, list: List[A]): List[A] =
list match {
case x :: xs if !xs.isEmpty => x :: s :: separate(s, xs)
case _ => list
}
/* reverse CharSequence */
class Reverse(text: CharSequence, start: Int, end: Int) extends CharSequence
{
require(0 <= start && start <= end && end <= text.length)
def this(text: CharSequence) = this(text, 0, text.length)
def length: Int = end - start
def charAt(i: Int): Char = text.charAt(end - i - 1)
def subSequence(i: Int, j: Int): CharSequence =
if (0 <= i && i <= j && j <= length) new Reverse(text, end - j, end - i)
else throw new IndexOutOfBoundsException
override def toString: String =
{
val buf = new StringBuilder(length)
for (i <- 0 until length)
buf.append(charAt(i))
buf.toString
}
}
/* iterate over chunks (cf. space_explode/split_lines in ML) */
def chunks(source: CharSequence, sep: Char = '\n') = new Iterator[CharSequence]
{
private val end = source.length
private def next_chunk(i: Int): Option[(CharSequence, Int)] =
{
if (i < end) {
var j = i; do j += 1 while (j < end && source.charAt(j) != sep)
Some((source.subSequence(i + 1, j), j))
}
else None
}
private var state: Option[(CharSequence, Int)] = if (end == 0) None else next_chunk(-1)
def hasNext(): Boolean = state.isDefined
def next(): CharSequence =
state match {
case Some((s, i)) => { state = next_chunk(i); s }
case None => throw new NoSuchElementException("next on empty iterator")
}
}
/* simple dialogs */
private def simple_dialog(kind: Int, default_title: String)
(parent: Component, title: String, message: Any*)
{
JOptionPane.showMessageDialog(parent,
message.toArray.asInstanceOf[Array[AnyRef]],
if (title == null) default_title else title, kind)
}
def dialog = simple_dialog(JOptionPane.PLAIN_MESSAGE, null) _
def warning_dialog = simple_dialog(JOptionPane.WARNING_MESSAGE, "Warning") _
def error_dialog = simple_dialog(JOptionPane.ERROR_MESSAGE, "Error") _
/* timing */
def timeit[A](message: String)(e: => A) =
{
val start = System.currentTimeMillis()
val result = Exn.capture(e)
val stop = System.currentTimeMillis()
System.err.println(
(if (message.isEmpty) "" else message + ": ") + (stop - start) + "ms elapsed time")
Exn.release(result)
}
}