Functional Programming Example in Dart

For a quick reference.

At the time of writing (Feb 2014), the top results from a Google search on ‘Dart functional programming’ or ‘Dart list comprehension’ don’t immediately yield clear examples. That’s crazy given that Dart is such a boss language. So here’s an example:

// double all values
List myList = [1, 2, 3, 4];
List doubledList = myList.map((x) => x * 2);

You can do the standard map, reduce, filter on Iterables on Dart. Of course you can chain them up like other languages. Although it’s not strictly using the set building notation like in Python, you can still pretty much do everything so something like:

[x * 2 for x in myList if x % 2 == 0]

in Python would look like:

myList.where((x) => x % 2 == 0).map((x) => x * 2);