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    copied!<p>Yes, you can emulate this with implicits and custom operators. Here is a short example:</p> <pre><code>implicit class FloatWrapper(n:Float) { def :&lt;(that:Float) = ResultAndLastItem(n&lt;that, that) def :&gt;(that:Float) = ResultAndLastItem(n&gt;that, that) def :=(that:Float) = ResultAndLastItem(n==that, that) // insert more comparison operations here } case class ResultAndLastItem(result:Boolean, lastItem:Float) extends FloatWrapper(lastItem) { // insert boolean operations here // boolean operations should return another instance of ResultAndLastItem (?) } implicit def toBoolean(r:ResultAndLastItem):Boolean = r.result </code></pre> <p>Here is an example usage in the REPL:</p> <pre><code>Welcome to Scala version 2.10.0 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_45). Type in expressions to have them evaluated. Type :help for more information. scala&gt; :paste // Entering paste mode (ctrl-D to finish) implicit class FloatWrapper(n:Float) { def :&lt;(that:Float) = ResultAndLastItem(n&lt;that, that) def :&gt;(that:Float) = ResultAndLastItem(n&gt;that, that) def :=(that:Float) = ResultAndLastItem(n==that, that) // insert more comparison operations here } case class ResultAndLastItem(result:Boolean, lastItem:Float) extends FloatWrapper(lastItem) { // insert boolean operations here // boolean operations should return another instance of ResultAndLastItem (?) } implicit def toBoolean(r:ResultAndLastItem):Boolean = r.result // Exiting paste mode, now interpreting. warning: there were 1 feature warnings; re-run with -feature for details defined class FloatWrapper defined class ResultAndLastItem toBoolean: (r: ResultAndLastItem)Boolean scala&gt; if(2 :&lt; 3 :&lt; 4) "yay" else "nope" res0: String = yay scala&gt; if(2 :&lt; 3 :&lt; 3) "nope" else "yay" res1: String = yay </code></pre> <p>Remarks:</p> <ul> <li><p>You can easily add more comparison operators, such as <code>:&lt;=</code>.</p></li> <li><p>The usage of custom operators is required because this forces the compiler to use the <code>implicit class</code> above, instead of the built-in default operator for <code>Float</code>s.</p></li> <li><p>It is hard to make my example more generic, in order to allow for all comparable types, such as <code>Double</code>, <code>Int</code>, or custom types. The reason why this is hard is because the <code>implicit class FloatWrapper</code> cannot require further <code>implicit</code> arguments - implicits cannot be nested. (Or more precisely, they can, syntactically, but then the compiler won't pick them for implicit resolution.)</p></li> <li><p>As an optimization, you might want to consider adding boolean shortcuts, i.e. when an expression is already known to be <code>false</code>, it is not necessary to evaluate the remaining comparisons.</p> <ul> <li>This becomes tricky when you also add boolean operators, such as <code>||</code> or <code>&amp;&amp;</code>.</li> </ul></li> </ul>
 

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