Reduce array to set in Swift

arrays swift set reduce
Banana picture Banana · Dec 8, 2015 · Viewed 56.5k times · Source

I am trying to reduce an array of objects to a set in Swift and this is my code:

objects.reduce(Set<String>()) { $0.insert($1.URL) }

However, I get an error:

Type of expression is ambiguous without more context.

I do not understand what the problem is, since the type of URL is definitely String. Any ideas?

Answer

NRitH picture NRitH · Dec 8, 2015

You don't have to reduce an array to get it into a set; just create the set with an array: let objectSet = Set(objects.map { $0.URL }).

Related questions

Swift Set to Array

An NSSet can be converted to Array using set.allObjects() but there is no such method in the new Set (introduced with Swift 1.2). It can still be done by converting Swift Set to NSSet and use the allObjects() method but …

Read More
Split a String into an array in Swift?

Say I have a string here: var fullName: String = "First Last" I want to split the string base on white space and assign the values to their respective variables var fullNameArr = // something like: fullName.explode(" ") var firstName: String = fullNameArr[0] var …

Read More
How to find index of list item in Swift?

I am trying to find an item index by searching a list. Does anybody know how to do that? I see there is list.StartIndex and list.EndIndex but I want something like python's list.index("text").

Read More