substr respecting single byte strings
substr respecting single byte strings

- substr respects mixed unicode and single byte characters
- does not corrupt length of the strings
- does not need encoding

peachpiecompiler/peachpie,iolevel/peachpie-concept,iolevel/peachpie,peachpiecompiler/peachpie,peachpiecompiler/peachpie,iolevel/peachpie-concept,iolevel/peachpie-concept,iolevel/peachpie,iolevel/peachpie