From: Iain Barnett <iainspeed@...>
Date: 2011-03-25T14:33:55+09:00
Subject: Re: shortcut for add unless nil ?


On 24 Mar 2011, at 22:45, Ryan Davis wrote:

> The most idiomatic (and performant) shortcut is to not have the situation arise in the first place. Nil checks everywhere is generally a design smell. Push things up to whereever the defaults should be figured out... in railsy parlance:
> 
>    thingies = params[:thingies] || []
> 
> then later you never have to worry about it.
> 

I agree to an extent, but even when you're defining defaults it would be nice:

    thingies = params[:thingies] || []
    wotsits =  params[: wotsits] || []
    stuff = thingies + wotsits

isn't as nice as
 
    stuff = params[:thingies] +? params[:wotsits]

where +? is my new infix operator of choice for "add unless nil" :) Sometimes I don't want the extra typing or to use extra locals that will only be used for that one line.


Iain