How do you assign a variable with the result of a if..else block?

Question

I had an argument with a colleague about the best way to assign a variable in an if..else block. His orignal code was :

@products = if params[:category]   Category.find(params[:category]).products else   Product.all end 

I rewrote it this way :

if params[:category]   @products = Category.find(params[:category]).products else   @products = Product.all end 

This could also be rewritten with a one-liner using a ternery operator (? :) but let's pretend that product assignment was longer than a 100 character and couldn't fit in one line.

Which of the two is clearer to you? The first solution takes a little less space but I thought that declaring a variable and assigning it three lines after can be more error prone. I also like to see my if and else aligned, makes it easier for my brain to parse it!

Answer 1

As an alternative to the syntax in badp's answer, I'd like to propose:

@products =    if params[:category]     Category.find(params[:category]).products   else     Product.all   end 

I claim this has two advantages:

1. Uniform indentation: each level of logical nesting is indented by exactly two spaces (OK, maybe this is just a matter of taste)
2. Horizontal compactness: A longer variable name will not push the indented code past the 80 (or whatever) column mark

It does take an extra line of code, which I would normally dislike, but in this case it seems worthwhile to trade vertical minimalism for horizontal minimalism.

Disclaimer: this is my own idiosyncratic approach and I don't know to what extent it is used elsewhere in the Ruby community.

Edit: I should mention that matsadler's answer is also similar to this one. I do think having some indentation is helpful. I hope that's enough to justify making this a separate answer.