In VS I am told this function “does not return a value in all control paths.” A bot told me specifically the issue is with this line: else if (letter + key <= 90). It said that if the outcome results in letter + key equally exactly 90 then a value is not returned, but I thought that was covered where ‘<=’ means ‘less than or equals.’

char rotate(char letter, int key)
{
    if (isalpha(letter) == true)
    {
        if (letter + key > 90)
        {
            int overage = letter + key - 90;
            letter = 64 + overage;

            while (letter > 90)
            {
                overage = letter - 90;
                letter += overage;
            }

            return letter;
        }

        else if (letter + key &lt;= 90)
        {
            letter += key;
            return letter;
        }
    }

    else if (isalpha(letter) == false)
    {
        return letter;
    }
  • @towerful
    21•8 months ago

    I’m a fan of early returns.
    So

    if(isalpha(letter) == false) return letter
if(letter whatever) {
   Do thing
   Return letter
}
if(letter something else) {
   Do something else
   Return letter
}
throw error("unprocessable letter")

    I find it lets me mentally walk through all the paths more easily.
    And if something gets too complex for this, then I need to break it down into further functions