Ruby Null-Conditional operator

Question

C# has a null-conditional operator that works like this

SomeObject?.SomeParam

If SomeObject is null, then the result of that expression will be null rather than throwing a null reference exception. Does something like this exist in Ruby?

You're right. I tried searching for this before, but couldn't find anything. Sorry about that. — Nashenas, Mar 19 '16 at 13:55

score 8 · Accepted Answer · answered Mar 18 '16 at 14:44

8

Yes. Use &. to call a method.

some_value&.some_method

If some_value is nil, then some_method will not be executed, and the return value of the expression will be nil. Otherwise, some_method will be called as with when called with ..

answered Mar 18 '16 at 14:44

sawa

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Do you have a link to `&.` documentation? – Emil Laine Mar 18 '16 at 14:49
No, I looked up in http://ruby-doc.org/core-2.3.0/doc/syntax/calling_methods_rdoc.html, but it seems the official document for that is not ready yet. – sawa Mar 18 '16 at 14:54
4

http://docs.ruby-lang.org/en/2.3.0/NEWS.html describes it briefly – Stefan Mar 18 '16 at 15:15

score 0 · Answer 2 · answered Mar 18 '16 at 14:43

0

If you are using Rails or ActiveSupport there is try, but there is nothing in the Ruby stdlib.

answered Mar 18 '16 at 14:43

Paul A Jungwirth

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The "safe navigation operator" is quite new - it was added in Ruby 2.3 – Stefan Mar 18 '16 at 15:19

Ruby Null-Conditional operator

2 Answers2