On 24 April 2017 at 18:27, Dilwyn Jones <dil...@evans1511.fsnet.co.uk>

> When SBASIC was first mooted, I remember that there was at the time
> discussion that other BASICs gave variables default zero value rather than
> stopping with an error - "why couldn't the QL do this?"
> Don't know if that influenced Tony Tebby to make SBASIC variables behave
> in this way or not, or was that just coincidence?

I've been struggling with this issue too when adapting the Spectrum's BASIC
for BASICODE, which was largely based on M$ BASIC. This allowed default
values for variables, which broke computers like the Spectrum and BBC. The
official BASICODE spec required proper initialisation of variables but this
was a common mistake among programmers that went undetected many times
because of poor testing before airing (obviously they used a C64 as testing
machine ;)). Since my adapted BASIC was expected to be used mainly to run
existing programs I decided to allow defaults (and leave out syntax checks
at entry too).

So, default variable values might probably be a good thing to run BASIC
programs converted from other platforms, but a bad thing when developing
your own.

*Jan Bredenbeek* | Hilversum, NL | j...@bredenbeek.net
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