Cannot convert value of type Substring to expected argument type String - Swift 4

Question

Trying to get substring of String and append it to array of Strings:

var stringToSplit = "TEST TEXT"
var s = [String]()
let subStr = anotherString[0 ..< 6]
s.append(subStr) // <---- HERE I GET THE ERROR

Just initialize a new String with your substring `s.append(String(subStr))` — Leo Dabus, Sep 22 '17 at 06:19

score 45 · Accepted Answer · edited Sep 22 '17 at 08:36

45

As @Leo Dabus mentioned, you need to initialize a new String with your substring:

Change:

s.append(subStr)

To:

s.append(String(subStr))

edited Sep 22 '17 at 08:36

MBH

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answered Sep 22 '17 at 06:23

Rashwan L

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Awesome - I was having difficulty figuring out how to convert a String.subsequence but this is simple and effective. Take my upvote – vikzilla Jan 11 '18 at 02:57

score 2 · Answer 2 · answered Feb 02 '22 at 19:22

my two cents for serro in different context. I was trying to get an array of "String" splitting a string. "split" gives back "Substring", for efficiency reason (as per Swift.org litre).

So I ended up doing:

let buffer = "one,two,three"
let rows = buffer.split(separator:",")

let realStrings = rows.map { subString -> String in
    return String(subString)
}

print(realStrings)

Ape can help someone else.

Cannot convert value of type Substring to expected argument type String - Swift 4

2 Answers2