String to kebab-case with SCSS/SASS - sass

Question

With a little help from this gist, I now have a function for kebab-casing a string in SCSS:
#function replace($string, $substr, $newsubstr, $all: 0) {
$string: quote(#{$string});
$substr: quote(#{$substr});
$newsubstr: quote(#{$newsubstr});
$position-found: str-index($string, $substr);
$processed: ();
#while ($position-found and $position-found > 0) {
$length-substr: str-length($substr);
#if (1 != $position-found) {
$processed: append($processed, str-slice($string, 0, $position-found - 1));
}
$processed: append($processed, $newsubstr);
$string: str-slice($string, $position-found + $length-substr);
$position-found: 0;
#if ($all > 0) {
$position-found: str-index($string, $substr);
}
}
$processed: append($processed, $string);
$string: "";
#each $s in $processed {
$string: #{$string}#{$s};
}
#return $string;
}
#function kebabCase($string) {
$replace: " ", "-", "–", "—", "_", ",", ";", ":", ".", "+", "=", "?", "&", "*", "/", "|", ">", "<", "(", ")";
#each $char in $replace {
$string: replace($string, $char, "-", 1);
}
#return $string;
}
My only problem is, this does not work with "camelCased" or "PascalCased" strings. For example this:
.example {
#{kebabCase("justify content")}: 'center'; // Works
#{kebabCase("justifyContent")}: 'center'; // Does not work
}
produces:
.example {
justify-content: "center";
justifyContent: "center";
}
My question: Is there any way SCSS can detect capital letters, so I can break words at their position (if it is not the first letter is a string)? I am not looking for a JS-solution, SCSS only.