Should be something like this:

```
if (self.modifiers)
{
    NSString *s = [NSString stringWithFormat:@"%@%@%@%@%@",
            (aModifierFlags & NSCommandKeyMask ? SRLoc(@"Command-") : @""),
            (aModifierFlags & NSAlternateKeyMask ? SRLoc(@"Option-") : @""),
            (aModifierFlags & NSControlKeyMask ? SRLoc(@"Control-") : @""),
            (aModifierFlags & NSShiftKeyMask ? SRLoc(@"Shift-") : @"")];
    return [s stringByReplacingCharactersInRange:NSMakeRange(s.length - 1, 1) withString:@""];
}
else
    return @""
```