Created
April 12, 2012 17:25
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when operator in scala
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/** | |
* A syntactic sugar corresponding to the Lisp's when. Execute the body | |
* when the pred evaluates to true. | |
* @param condition A predicate or value that evaluate to a Boolean | |
* @param block A valid block of scala code | |
*/ | |
def when (condition : => Boolean)( block : => Unit) | |
{ | |
if (condition){ block } | |
} | |
//A left associative version from the redditor elbowich | |
implicit def `when for function0`[A](f: => A) = new { | |
def when(cond: Boolean) = if(cond) Some(f) else None | |
} |
Yep! Thanks for the suggestion!
Bye!
Alfredo
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This is great for side effect driven code, but this may also be useful to you for code that you care about the return value ( which should be most of the time :) ):
I'm not quite sure whether this is useful to you, but it may be an interesting thing if you're new to Scala and couldn't quite figure out how you would return a value from when without returning a blasphemous 'null' value. ;)
Happy Scala-ing!