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The string literals can be extracted from a constant array after applying the flatMap operation on it by using filter or compactMap functions of Swift.
The filter function can be used to filter out any non-string literals or nil values from the array. For example:
let array = [1, "two", 3, "four", nil, "five"]
let strings = array.flatMap { $0 as? String }
let filteredStrings = strings.filter { $0 != nil }
print(filteredStrings) // ["two", "four", "five"]
The compactMap function can be used to both map and filter out any non-string/literal values or nil values from the array in one step. For example:
let array = [1, "two", 3, "four", nil, "five"]
let strings = array.compactMap { $0 as? String }
print(strings) // ["two", "four", "five"]