A couple of times I have been asked “How would you do X in functional programming?” I absolutely love these types of questions. I do my best to answer every question, but I think there are many questions interesting enough to warrant their own articles. So for this article I would like to demonstrate how I could recreate this imperative function in a more functional manner. This function has an statement without an . So while a operator could work, it is not ideal. if else ternary Here we need to run `dispatch` only when we have a `value`, otherwise we do nothing. One option is to use a short circuit operator: Short circuit and ternary and both ways you can solve this problem, but let’s take a look at a couple more. Solution A: ifVal Helper Function To do this in a more functional way, I will create a helper function. I’ll write this helper old school first then boil it down piece by piece so everyone can understand it easily. Now we can modify our function to use instead of the classic block. someAction ifVal if Here’s the comparison for a quick and easy twitter screenshot: Further reading Take a look at Ramda’s , , and for other useful and similar functions. when unless ifelse Solution B: Functors We could also use the . The Maybe Type consists of either a type which holds a value or a type which is exactly what is says. Maybe Type Just Nothing For this example, I’ll use the Maybe Type from the library. Sanctuary It looks a little like this: The Maybe Type is pretty simple and the reason why I want to use it is because and work together so well, it was been given a special name, a . map Maybe Functor Some libraries like have a fluent syntax, but this article is using Sanctuary. Though, it is good to know that these two are equivalent. ramda-fantasy Examples: All together with the Maybe will look like this: doSomething Here we have three functions, , and that can be composed together into a new single function. We can pass value into that new function and it will flow through first into , then and finally that value will flow into our . getItem toMaybe map getItem toMaybe map And for one last picture perfect Tweet: End I hope you enjoyed this small functional journey. Let me know in the comments if you did, if you got lost, if you have any questions, or if you want more articles like this one. If you really want to motivate me, follow me here or and if you this article, pass it around! Twitter loved Cheers! p.s. this article was . originally posted on dev.to

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