64 bit integers in BASIC

I would like to use 64 bit integers in BASIC. I don’t think all integers should be 64 bit – that would be wasteful. I would like to see them as an additional data type.

What would the syntax be?

When a 32 bit integer is assigned to a 64 bit, I assume it would be sign extended, so if we wanted to take an inherently unsigned one (such as a file position or extent), we would have to explicitly AND with FFFFFFFF.

I assume we could indirect them with two pling operations, one shifted.

BB4W supports (signed) 64bit integers, using %% as the name suffix. So it would probably make sense if we followed their lead.

Using 64bit integers with SYS could be fiddly. Maybe it can borrow a leaf from VDU’s book and use ‘|’ instead of ‘,’ whenever we want a 64bit value? E.g.

SYS "OS_Something",A%%,A%%>>32,C% TO B%,B2% : B%%=B%+(B2%<<32)

Could be written as

SYS "OS_Something",A%%|C% TO B%%|

I.e. whether for input or output, | will cause the preceeding variable to be treated as a 64bit value split across two consecutive registers.

(In reference to VDU, ‘;’ would have been a more obvious choice for a double-width value, but of course that’s already been made use of for capturing the NZCV flags on return)

Two things to consider:

Firstly, I have seen AND -1 used as a shortcut to writing &FFFFFFFF so breaking this behaviour might cause some weird crashes, because &FFFFFFFFFFFFFFFF != &FFFFFFFF.

Secondly, is there any OS level API that is capable of displaying and manipulating 64 bit values? I’m thinking here of the likes of OS_ConvertXXX and the like. Of course, we also hit the problem that a 64 bit value can’t be represented in a single register…

Secondly, is there any OS level API that is capable of displaying and manipulating 64 bit values? I’m thinking here of the likes of OS_ConvertXXX and the like. Of course, we also hit the problem that a 64 bit value can’t be represented in a single register…

OS_ConvertVariform

The most recent RiscLua (6.xx) has 64 bit integers. They are cut down to 32-bit for sys calls.

I would like to use 64 bit integers in BASIC.

I wrote a library to support some of this this, as have others. It is a candidate for Basalt, someday. ;-)

Look at http://kappa.me.uk/Libraries/lbLongs032.zip