Re: CiderPress v2.3.1 released

[pausch@saaf.se (Paul Schlyter)]

In article <jLCdnaXfctDnsTTeRVn-rw@comcast.com>,
Michael J. Mahon <mjmahon@aol.com> wrote:

> Shawn B. wrote:
>>>New features:
>>>- Import Applesoft BASIC programs from text files.  A text listing with
>>> one line of Applesoft code per file line can be directly converted to
>>> a BAS file on a disk image or ShrinkIt archive.
>> 
>> 
>> though the BASIC import is very very nice, you should prompt upon syntax 
>> errors.  In a 200+ line program I typed in from Nibble, I can't tell you how 
>> many illegal characters or bad syntax issues got imported in.  Anyway, good 
>> work.  I still hope you can detect syntax issues during import and prompt me 
>> before I have to keep going to the emulator and figuring out what the 
>> problem is.
> 
> Welcome to Applesoft!  That's exactly how it works on an Apple!
> 
> Syntax is only checked when you attempt to execute a line.
> This is not unusual for interpreters.
> 
> It's part of the reason that Nibble and others had checksum
> programs that verified that each line or group of lines was
> OK.

In this respect, Integer Basic was much better: it actually parsed
each line when input, and refused to accept it if it contained a
syntax error.  Its syntax error messages were also much more
informative than just a "Syntax error".

Therefore, implementing an "Import Integer Basic program from text files"
function in Ciderpress would be much more dufficult - and in addition,
not every text file can be imported as Integer Basic, even if each line
starts with a line number.


Applesoft lax syntax checking also allowed some oddities, like:

 20 IF A <=> B THEN .....

Of course "A <=> B" always evaluated as "true" since every number is
always less than, equal to, or greater than, every other number.

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