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Safer JavaScript with the Maybe Type

Safer JavaScript with the Maybe Type


    Safely Access Object Properties with `prop`

    Andy Van SlaarsAndy Van Slaars

    In this lesson, we’ll use a Maybe to safely operate on properties of an object that could be undefined. We’ll use our initial code as the basis for a prop utility function that can be reused with different objects and various property names. Instead of just blindly asking for a property, this version of prop will drop us into the safe confines of a Maybe, giving us a Just when the property exists and a Nothing for an undefined property. Once we’ve built up our own prop utility, we’ll refactor the code one more time to take advantage of the built-in prop utility provided by the crocks library.

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