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iOS Closures in Swift 2 First Class Functions Review: First Class Functions

Darcy Phillips
Darcy Phillips
4,087 Points
Posted by Darcy Phillips
Darcy Phillips
4,087 Points

higher order function question

The question is:

A higher order function is a special function that only takes certain parameter types.

I answered true. I don't understand why my answer is not accepted as correct. A higher order function is in fact one that only takes certain parameter types, those parameter types being: ones that have function signatures. If the function does not take function signatures as one of it's parameter types then it's not a higher order function. Is that not true?

2 Answers

Oliver Duncan
Oliver Duncan
16,642 Points
Oliver Duncan
Oliver Duncan
16,642 Points

You're right in a way, but it doesn't only take parameters with function signatures. It can also take any number of other parameters of different types. In other words the only requirement for a function to be a higher order function is that it either takes a function, or returns one, or both - it doesn't restrict its parameter types to only functions.

Darcy Phillips
Darcy Phillips
4,087 Points
Darcy Phillips
Darcy Phillips
4,087 Points

Ah, now I see what they're getting at with that. Thank you for that clarification!