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Ruby Ruby Collections Ruby Arrays Ruby Arrays

Posted by Ryan Egan
Ryan Egan
5,324 Points

Why are there no commas between elements when using %W()?

Jason writes %W(milk eggs bread), why is there no need to add commas between each element? What happens if you want an element to have a space? Would you just add \s?

1 Answer

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points
Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

There are two ways to add spaces:

%w(yes no I\ don't\ know)

or 

%W(yes no #{I don't know})

Notice that the second method requires the capital W. The first one works with both uppercase and lowercase W. It's like single and double quotes.

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points
Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

This is just short and fancy way of making an array of strings.

Ryan Egan
Ryan Egan
5,324 Points

So it is assuming that you are trying to add multiple one word strings?

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points
Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

It's assuming you are adding strings without requiring you to use quotes or commas :). Spaces between the words are the only thing that requires an extra mile. But yeah, most use cases I've seen are lists of single words.

Ryan Egan
Ryan Egan
5,324 Points

Excellent! Thanks for the help :)

Manas sricharan VARRI
Manas sricharan VARRI
8,242 Points

hi maciej czuchnowski , thanks for sharing your advice for using spaces. i just wanted to ask that second method which u said isn't working for me. %W(yes no #{I don't know}). we can interpolate only variables that are already declared right?

rowend rowend
rowend rowend
2,926 Points
rowend rowend
rowend rowend
2,926 Points

Manas sricharan VARRI Yes, you can only interpolate with variables declared previously. Or inside of interpolation sintax set the ruby expression to evaluate like: "#{5 + 1}"