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docs/_style/prism-master/examples/prism-scala.html
100 строк2 KB
CyC2018
use prism-tomorrow.css
19 дек 2018, 09:09
19 дек 2018, 09:09e9e604e
<h2>Comments</h2>
<pre><code>// Single line comment
/* Mutli-line
comment */</code></pre>

<h2>Strings and characters</h2>
<pre><code>'a'
"foo bar baz"
"""Multi-line
string"""</code></pre>

<h2>Numbers</h2>
<pre><code>0
21
0xFFFFFFFF
-42L
0.0
1e30f
3.14159f
1.0e-100
.1
</code></pre>

<h2>Symbols</h2>
<pre><code>'x
'identifier</code></pre>

<h2>Full example</h2>
<pre><code>// Contributed by John Williams
package examples

object lazyLib {

  /** Delay the evaluation of an expression until it is needed. */
  def delay[A](value: => A): Susp[A] = new SuspImpl[A](value)

  /** Get the value of a delayed expression. */
  implicit def force[A](s: Susp[A]): A = s()

  /**
   * Data type of suspended computations. (The name froms from ML.)
   */
  abstract class Susp[+A] extends Function0[A]

  /**
   * Implementation of suspended computations, separated from the
   * abstract class so that the type parameter can be invariant.
   */
  class SuspImpl[A](lazyValue: => A) extends Susp[A] {
    private var maybeValue: Option[A] = None

    override def apply() = maybeValue match {
      case None =>
        val value = lazyValue
        maybeValue = Some(value)
        value
	  case Some(value) =>
        value
    }

    override def toString() = maybeValue match {
      case None => "Susp(?)"
      case Some(value) => "Susp(" + value + ")"
    }
  }
}

object lazyEvaluation {
  import lazyLib._

  def main(args: Array[String]) = {
    val s: Susp[Int] = delay { println("evaluating..."); 3 }

    println("s     = " + s)       // show that s is unevaluated
    println("s()   = " + s())     // evaluate s
    println("s     = " + s)       // show that the value is saved
    println("2 + s = " + (2 + s)) // implicit call to force()

    val sl = delay { Some(3) }
    val sl1: Susp[Some[Int]] = sl
    val sl2: Susp[Option[Int]] = sl1   // the type is covariant

    println("sl2   = " + sl2)
    println("sl2() = " + sl2())
    println("sl2   = " + sl2)
  }
}</code></pre>

<h2>Known failures</h2>
<p>There are certain edge cases where Prism will fail.
	There are always such cases in every regex-based syntax highlighter.
	However, Prism dares to be open and honest about them.
	If a failure is listed here, it doesn’t mean it will never be fixed. This is more of a “known bugs” list, just with a certain type of bug.
</p>

<h3>Nested block comments</h3>
<pre><code>/* Nested block
	/* comments
	are */
not supported */</code></pre>