InitializerList literal

InitializerList Literal

InitializerList literals are a list of values surrounded by curly braces and separated by commas:

{1, 2, 3, 4, 5, 6}

{'A'ub, 'B'ub, 'C'ub, 'D'ub, 'E'ub, 'F'ub}

{"Apples", "Bananas", "Oranges", "Grapes", "Peaches"}

Result Type

InitializerList literals have the type of <$T> InitializerList where $T is the type of the first element:

Example	Result Type
{1, 2, 3, 4, 5, 6}	<long> InitializerList
{1us, 2, 3, 4, 5, 6}	<ushort> InitializerList
{{1, 2, 3} as <int> Array, {1, 2, 3}, {1, 2, 3}}	<<int> Array> InitializerList

Automatic User-Defined Conversions

In order for InitializerList values to properly convert to other types, user-defined conversions must be created. In the following example, we provide a user-defined conversion that allows InitializerList literals to be automatically converted to a custom array type:

import InitializerList

struct <$T> MyArray (items *$T, length usize)

implicit func __as__(list <$T> InitializerList) <$T> MyArray {
    my_array POD <$T> MyArray
    my_array.items = list.array
    my_array.length = list.length
    return my_array
}

func main {
    values <long> MyArray = {1, 2, 3, 4, 5}
}