Idiom #340 Last character of string

Assign to c the value of the last character of the string s.

Explain the type of c, and what happens if s is empty.

Make sure to properly handle multi-bytes characters.

Rust

let c = s.chars().last().unwrap();

Demo
Doc

char c = s[^1];

final c = s[s.length - 1];

Demo
Doc

r := []rune(s)
c := r[len(r)-1]

Demo

import "unicode/utf8"

c, _ := utf8.DecodeLastRuneInString(s)

Demo
Doc

lastChar :: String -> Char
lastChar s
    | s=="" = ""
    | otherwise = s !! (length s - 1)

import static java.lang.Character.isSurrogate;

int n = s.length(), i = n - 1;
if (isSurrogate(s.charAt(i))) --i;
String c = s.substring(i);

LazUtf8

function GetLastUtfCodePoint(const S: String): String;
var
  p: PChar;
  PLen: PtrInt;
begin
  Result := '';
  p := UTF8CodepointStart(PChar(S), Length(S), Utf8Length(S) - 1);
  PLen := UTF8CodepointSize(p);
  Result := p;
  SetLength(Result,PLen);
end; 

var
  s: string;
begin
  c := GetLastUtfCodePoint(s);
end.