C++ today is as simple as BASIC was in the 80s

Single header BASIC emulation in C++. This is based on my (flawed) memory of the BASIC dialect in the EACA Colour Genie computer I got on my 15th birthday.

Example program:

#include "basic.hpp"

int main()
{
  _10: LET X = 1;
  _20: LET SUM = 0;
  _30: LET DEPTH = 1;
  _40: INPUT "Enter a positive number: ", X;
  _50: IF X > 0 THEN GOTO _130;
  _60: PRINT "By positive, I mean greater than zero. You entered ", X, " which isn't";
  _70: GOTO _40;
  _80: SUM = SUM + X;
  _90: X = X - 1;
 _100: IF X > 0 THEN GOSUB _80;
 _110: DEPTH = DEPTH * 2;
 _120: RETURN;
 _130: GOSUB _80;
 _140: PRINT "SUM=", SUM, " DEPTH=", DEPTH;
}

Limitations

• Only numeric variables are supported (no strings, no matrices)
• C++11 or later (easy to back-port, but why?)
• Those pesky semicolons...
• Variables must be defined prior to use
• Can't be used in kernel modules ;-)
• Many language features missing, e.g. PRINT USING and Most I/O

PR's for fixes and added functionality are most welcome.