In object-oriented programming, the safe navigation operator (also known as optional chaining operator, safe call operator, null-conditional operator, null-propagation operator) is a binary operator that usually returns null if its first argument is null otherwise it performs a dereferencing operation as specified by the second argument instead of throwing an error.

Ruby

In Ruby

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if event && event.details && account.details.venue
 return account.details.venue
end

can be written as

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return event&.details&.venue

using the safe navigation operator (&.) which was a nice addition after Ruby 2.3.0.

Javascript

In JS, safe navigation is caled optional chaining. The optional chaining (?.) operator accesses an object’s property or calls a function. If the object accessed or function called using this operator is undefined or null, the expression gets bypassed and evaluates to undefined instead of throwing an error.

For example:

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const place = event && event.details && event.details.venue;

can be written as

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const place = event?.details?.venue