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Agustin Hernandez
2,747 PointsCreating Empty Arrays
What's the difference when declaring an empty array
// like this
var someArray: [SomeType]
// Or like this
var someArray = [SomeType]()
2 Answers
Alex Koumparos
Python Development Techdegree Student 36,862 PointsIn the first case:
var someArray: [SomeType]
You have declared but not initialised your array. If you wanted to use this style to declare an empty array, you would have written:
var someArray: [SomeType] = []
The second case:
var someArray = [SomeType]()
is exactly equivalent to var someArray: [SomeType] = []. The difference is purely personal style preference.
Apple uses both in their own documentation, see here and here
johntheofanopoulos4
iOS Development with Swift Techdegree Student 474 PointsFirst line is that you have declared your array but didn't assign anything (technically you just gave a name but no value)
Second line of code, you have named your array and assigned an empty/placeholder value in it.