src/Pure/library.scala

moved Library.decode_permissive_utf8 to Isabelle_System;
moved Library.with_tmp_file to Isabelle_System;
added Isabelle_System.read_file/write_file;
added Isabelle_System.system_out, with propagation of thread interrupts and process shutdown (global CTRL-C);

/*  Title:      Pure/library.scala
    Author:     Makarius

Basic library.
*/

package isabelle

import java.lang.System


object Library
{
  /* 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
    }
  }


  /* timing */

  def timeit[A](e: => A) =
  {
    val start = System.currentTimeMillis()
    val result = Exn.capture(e)
    val stop = System.currentTimeMillis()
    System.err.println((stop - start) + "ms elapsed time")
    Exn.release(result)
  }
}