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Level Up Your Ruby Skillz: Writing Compact Code

Molly Struve (she/her) on May 29, 2019

We have all been there, we issue a Pull Request(PR) that we feel is super tight and awesome. It gets stamped "Approved", but there is a catch. Our ...

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Abraham Williams • May 29 '19

One small optimization I like is when chaining methods:

array.select{|n| n.even?}

can be shortened to:

array.select(&:even?)

Molly Struve (she/her) • May 29 '19

100% Thanks for pointing that out! I copied it from the other tutorial without even thinking that I should optimize it. Good call.

Andrew Brown 🇨🇦 • May 29 '19 • Edited

So I was mentoring the ExamPro interns a few days ago with an introduction on Ruby and I was showing how malleable Ruby is and we came up with this meme.

Enrique Moreno Tent • May 31 '19

The last expression would give a different result if x were to be false instead on nil. Beware.

Andrew Brown 🇨🇦 • May 31 '19

This is why I didn't originally include it since someone such as yourself would have spotted this. ha

Molly Struve (she/her) • May 29 '19

😂That's fabulous!

Andrew Brown 🇨🇦 • May 30 '19

In retrospect, the third should have been

x = 1 unless x

Enrique Moreno Tent • May 31 '19 • Edited

Beware. This 2 lines do not do the same:

x = a.nil? ? b : a
x = a || b

Example:

a = false
b = "foo"

x = a.nil? ? b : a
# x = false

x = a || b
# x = "foo"

Nestor Custodio • May 30 '19

Might I suggest you relabel the "Inline Booleans" section to "Conditionals Can Be Used As Modifiers", as "modifier syntax" is what that feature of the language is actually called.

Would make it easier for those who want to look up additional information on that.

Molly Struve (she/her) • May 30 '19

Oh, thanks, I will add that!

Drew Bragg • Feb 21 '20

Now I want to go back to all my old code and refactor everything that says x = a if x.nil? into x ||= a That's so awesome.

Omri Gabay • May 29 '19

Really cool for beginning Rubyists. I use all of these daily (Thanks Rubocop!) except for Safety Navigator which I'll hopefully start using more now.

Francisco Quintero 🇨🇴 • May 31 '19

When I met Guard Clauses fell in love and now I can't stop looking for ways to use them and stop doing:

if condition
  # something
else
  # something else
end

Tyler Fisher • Jul 11 '19

This may be a month old, but I still use this cheat sheet nearly daily!

Molly Struve (she/her) • Jul 11 '19

YAY!!! I can't tell you how happy that makes me!!!! ❤️️

Tyler Fisher • Jul 11 '19 • Edited

I finally just threw it on my bookmark bar instead of relying on browser history which made me realize I should throw up a comment ^_^

Luke Duncan • May 31 '19

You've done it again! This is awesome.