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Ruby

Posted by Sebastian Velandia
Sebastian Velandia
24,676 Points

What is the exact function of the ? in the examples with all and any?

Hello in the example Jason explain with any and all I see this syntax

array1.all? {|item| item>3}

What is the function of the ? symbol in that sentence?

I mean, is the ? part of the name of the funcion all and any?

Because in the example with select Jason did not use the ? symbol

Maciej Czuchnowski
Maciej Czuchnowski
36,441 Points

Which video?

1 Answer

Geoff Parsons
Geoff Parsons
11,679 Points
Geoff Parsons
Geoff Parsons
11,679 Points

In ruby you can use ! and ? as part of your method names. They're some idiomatic suggestions as to when to use them but they do not affect how the method functions in any way - they're just part of the name.

Typically you would see methods ending in a question mark when they return true or false for a state such as string#empty?.

And you'd end a method in an exclamation point when it modifies the object it is acting on for example string#gsub vs string#gsub!.