E070: A radix prefix isn't followed by any digit

Turf lets you write integers in hexadecimal (0x), binary (0b), and octal (0o) as well as ordinary decimal:

mut hex: int = 0xFF;    // 255mut bin: int = 0b1010;  // 10mut oct: int = 0o17;    // 15

Each of these prefixes has to be followed by at least one real digit in that base. If it isn’t – because you stopped typing partway through, or left a stray 0x/0b/0o somewhere in your code – there’s nothing for the compiler to actually build a number out of:

mut x: int = 0x;   // ERROR: nothing after '0x'

The fix is almost always just finishing the literal you meant to write:

mut x: int = 0xFF;

If you didn’t mean to write a hex/binary/octal number at all, remove the prefix and write a plain decimal number instead.

Run turf --explain E070 in a terminal to read this again.