Date   : Wed, 01 Dec 1999 07:39:54 -0800 (PST)
From   : Angus Duggan <angus@...>
Subject: Re: Basic compiler 

James Gibbon writes:
>It's been a loooooong time since I played with BBC BASIC but
>if I remember correctly, ?n= would write a byte, !n= would 
>write 2 bytes (a signed integer?) where n is the address.  So
>if I'm right there's no provision to write reals directly to 
>memory, at least in the versions I was familiar with.

! is 4 bytes, and there are no indirection operator for reals. What I meant
in my badly worded message about "direct operators" is that there is no easy
way in the language. Reals are passed to machine code via CALL by address, so
it is easy to write a piece of machine code to take an integer and a real,
and store the real at that address. It doesn't look tidy in the code, though,
and the converse operation of reading the real back from an address cannot be
done as part of an expression (it must be a statement), because USR returns
an integer.

a.