I recently discovered that one can use the Pimp Enrich My Library pattern to add methods to companion objects using .type: object Whatever { } implicit class WhateverExtensions(val obj: Whatever....

In Scala 2.9 to add custom methods to a library class (enrich or "pimp" it) I had to write something like this: object StringPimper { implicit def pimpString(s: String) = new { def greet: String...

I've got a class from a library (specifically, com.twitter.finagle.mdns.MDNSResolver). I'd like to extend the class (I want it to return a Future[Set], rather than a Try[Group]). I know, of course...

I was trying to figure out how to write a functional swap function that works on any Traversable[_], given a collection and the indexes to swap. I came up with the following: def swap[A, CC <% ...

Scala 2.10 introduces value classes, which you specify by making your class extend AnyVal. There are many restrictions on value classes, but one of their huge advantages is that they allow extensio...

One of the most powerful patterns available in Scala is the enrich-my-library* pattern, which uses implicit conversions to appear to add methods to existing classes without requiring dynamic method...

When working with Java from Scala, we have to account for null. HttpServletRequest getters (getAttribute, getHeader, etc.) for example, all potentially return null. I know I can manually do a ca...

The are two different way to implement it. One is more short implicit def toR1(s:String) = new { def getLength = s.length)} Second is more long class R2(s:String){def getLength2 = s.length)} i...

Im looking to extended the iterator to create a new method takeWhileInclusive, which will operate like takeWhile but include the last element. My issue is what is best practice to extend the itera...

Say I have a method that turns a (function on two elements) into a (function on two sequences): def seqed[T](f: (T,T) => T): (Seq[T], Seq[T]) => Seq[T] = (_,_).zipped map f In words, the r...

The toInt method in StringLike doesn't take any arguments, and can only parse in decimal. So to parse binary, hex etc we need to resort to Java's Integer#parseInt(String s, int radix). In an attem...

Suppose one wants to build a novel generic class, Novel[A]. This class will contain lots of useful methods--perhaps it is a type of collection--and therefore you want to subclass it. But you want t...