Higher-Order Functions
Explore how to use higher-order functions in Dart by passing and returning functions as values. Learn to write reusable code with precise type signatures, apply transformations to collections, and understand built-in methods like forEach and map for effective iteration.
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Dart is a true object-oriented language. Because of this, functions themselves are objects and have a type of Function. We treat functions as first-class values. This means that, exactly like a string or a number, we can assign a function to a variable, pass it as an argument to another function, or return it as a result.
When a function accepts another function as a parameter, or returns a function as a result, we call it a higher-order function. This pattern allows us to write highly reusable logic.
Creating a higher-order function
Let us build a custom function called forAll. We want this function to accept a list of numbers and a transformation function. It will apply the transformation to every item and return an entirely new list. ...