convert function
Apply Arabic shape substitutions
Implementation
String convert(String input) {
final lines = input.split('\n');
final parsed = <String>[];
for (var i = 0; i < lines.length; i++) {
if (lines[i].isEmpty) {
continue;
}
parsed.addAll([..._parse(lines[i]), if (i != lines.length - 1) '\n']);
}
return parsed.join();
}