Rails ||= for empty strings

Question

The following code won't change the variable:

@my_var = ''
@my_var ||= 'This is a non-empty string'

Is there any nice/clean way to do this so that empty strings are overwritten?

Here, @my_var in not null. So, you've to do something like this: @my_var = 'This is a non-empty string' if @my_var.empty? or @my_var = 'This is a non-empty string' unless @my_var.present? — Emu
– Emu, Commented Oct 27, 2020 at 3:54
monkey patching can help you, stackoverflow.com/questions/647370/… — Raghav Garg
– Raghav Garg, Commented Oct 27, 2020 at 3:56
Other way you can set value as nil instead of ''(blank string) like => @my_var = ''.presence @my_var ||= 'This is a non-empty string' — Sampat Badhe
– Sampat Badhe, Commented Oct 27, 2020 at 3:59
If @my_var is undefined / not set, you should avoid empty string and just use nil instead. — Stefan
– Stefan, Commented Oct 27, 2020 at 7:36

Palash Bera · Accepted Answer · 2020-10-27 05:15:02Z

12

you can try like this:

@my_var = ''
@my_var = @my_var.presence || 'This is a non-empty string'

Thanks :-)

answered Oct 27, 2020 at 5:15

Palash Bera

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1 Comment

I didn't know that, great tip!

Oliver Gaida · Accepted Answer · 2020-10-27 05:45:04Z

1

in this case, i would just check the length of this string:

@my_var = ''
@my_var = 'This is a non-empty string' if @my_var.length == 0
=> "This is a non-empty string"

answered Oct 27, 2020 at 5:45

Oliver Gaida

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