DEV Community

loading...
Cover image for Neat way to handle array and individual inputs in same function

Neat way to handle array and individual inputs in same function

Saurabh Sharma
Web development React.js GraphQL Typescript JavaScript Design SEO
・1 min read

Lets say we need to make a function doSomething. we need to do it in a way so that it can handle both arguments: (1) a string and (2) an array of strings.

To achieve that previously I used to do something like this:

function doSomething(strs) {
  function _doSomething(str) {
    // some mysterious stuff happening here
    console.log(str)
  }

  if (Array.isArray(strs)) {
      return strs.map(str => _doSomething(str))
  } else {
      return _doSomething(strs)
  }
}

doSomething(["hello", "world"])
doSomething("hello")
Enter fullscreen mode Exit fullscreen mode

now since I learned recursion I do this:

function doSomething(strs) {
  if (Array.isArray(strs)) {
      return strs.map(str => doSomething(str))
  } else {
      console.log(strs);
  }
}

doSomething(["hello", "world"])
doSomething("hello")
Enter fullscreen mode Exit fullscreen mode

cover Photo by pepe nero on Unsplash

Discussion (2)

Collapse
bias profile image
Tobias Nickel

for a while i added something like this to my functions:

if (!Array.isArray(arg)) arg = [arg];

but typescript don`t like it.

Collapse
itsjzt profile image
Saurabh Sharma Author

Typescript doesnt know anything 😑