nemoBasic

For anyone interested in my development of BBC Basic, there’s a page here

It is not currently available for download though.

Looks like a pretty interesting set of changes there.

<reads> WTaF? Local and errors and… Holy crap, I wonder how many weird and obscure bugs that has been responsible for through the years.
🤦🏻‍♀️

And bear in mind that it applies to implicitly local vars as well as explicitly local, so this kind of thing is a Very Bad Idea:

DIMq%255
…
ONERROR:PROCreport
REPEAT:SYS"Wimp_Poll",mask,q% TO r
…
PROCsomething(q%+8)
…
DEFPROCsomething(q%)
SYS"This_MightError",“but that’s ok?”,q%
ENDPROC

Every time PROCsomething triggers an error, your Wimp block moves 8 bytes further through memory. Good luck.

this kind of thing is a Very Bad Idea

Ummm. It seems to me that it’s just one example of a whole, huge class of things that are Very Bad Ideas, many of which one might get away with, some of them consistently, others (more worryingly) almost all the time.

Something that is a good idea but 40 years too late is the ability to assemble code (or data) direct to file by setting O% to a file handle when using OPT4.

Seems obvious when written down:

>O%=OPENOUT"temp"OF"Utility"
>[OPT7:SWI"XOS_WriteS":=“Yup, this works”
>[OPT7:=13:=10:=0:ALIGN:MOV PC,R14:]
>CLOSE#O%
>*temp
Yup, this works
>

Seems obvious when written down:

That is really cool.

Ta. I’ve used that a few times now to knock up a little Utility in a few lines.

And this is as polymorphic as Basic gets, and is also really useful:

PRINTnum%,~IF​(T%=1<<30,SPC8,T%)," "name$

This decides mid-PRINT whether to display T% in hex or an empty column – featuring both IF and SPC in function form. This IF​() is therefore polymorphic (loosely typed) – as is FN​() of course – but though a polymorphic FN​() can reasonably be used anywhere, a polymorphic IF() is only useful in PRINT[#] because Basic generally has strongly-typed destinations.

I realise I am now modifying Basic to allow me to be even more terse.

Side note: A polymorphic FN​():

x=FNpoly​(1)
a$=FNpoly​(2)
…
DEFFNpoly​(type)
IFtype=1:=PI
=“pie”