Started introducing lexer and parser, added retarded workaround for
a retarded standard header's problem (namely, libc++'s unordered_set
and others including <math.h> - a GNU one, but that is kinda fine,
but that math.h retardingly introduces `log` into global namespace.
F*ck you, GNU. Sincerely, the world. Which era are we in that we can't
even have properly C++ aware headers? Also, why the f*ck the same
happens with <cmath> alone? F*ck you, the random person that decided
to allow standard C++ headers introduce ANYTHING into global namespace.
Sincerely, the world.)