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Re: Applesoft tokenization phases?

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On Thu, 12 Mar 2020 17:46:00 +0200, "Ev. Drikos" <drikosev@gmail.com>
wrote:

>This question relates to thread "Languages with Optional Spaces".
>
>In an Applesoft II manual I've found at "classiccmp.org" [1], page 7,
>we read that in a variable name any alphanumeric characters after the
>first two are ignored, unless they contain a reserved world. FEND ie
>would be illegal as it contains END.
>
>To implement such a rule one could first recognize keywords and then
>recognize any names. We see in p123 that stmt I is tokenized as II:
>  I.   stmt: 100 FOR A = LOFT OR CAT  To 15
>II. tokens: 100 FOR A = LOF TO RC AT To 15
>
>Yet, I've found ie a program at "hoist-point.com" [2] that contains:
>110 DIFF = ABS(A(I)-N)
>
>Also, an online AppleSoft simulator at calormen.com [3] accepts ie both
>DIFF and FEND as valid variable names.
>
>As it seems, this issue can affect a design choice for the tokenization
>phases of an Applesoft front-end. Is the manual just informative or the
>online simulator does not accept (precisely) the particular dialect?

I recall there being some minor differences between the disk based
AppleSoft BASIC on the Apple][ and ][+ (which required the additional
language card to run) and the ROM AppleSoft BASIC on the //e, //c, and
//gs.  But I no longer recall exactly what those differences were.

[ISTM the Apple /// also had a different ROM BASIC.]

Unfortunately, I no longer have my //e or //gs, or any of my old
AppleSoft BASIC code to look at.  But my [perhaps faulty] recollection
is that they did allow variable names to contain keywords as long as
the name did not begin with the keyword.

FWIW, I remember the //e AppleSoft manual having a different cover
[the //gs did not come with a BASIC manual].

My suspicion is that the manual that is at classiccmp.org is for the
original disk based version, but that the simulator is based on the
later ROM version.


YMMV,
George
[This is drifting into alt.folklore.computers territory. -John]

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Thread

Applesoft tokenization phases? "Ev. Drikos" <drikosev@gmail.com> - 2020-03-12 17:46 +0200
  Re: Applesoft tokenization phases? George Neuner <gneuner2@comcast.net> - 2020-03-13 17:55 -0400
  Re: Applesoft tokenization phases? awanderin <awanderin@gmail.com> - 2020-03-16 00:07 -0600
    Re: Applesoft tokenization phases? "Ev. Drikos" <drikosev@gmail.com> - 2020-03-18 00:14 +0200
      Re: Applesoft tokenization phases? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2020-03-20 07:06 -0400
        Re: Applesoft tokenization phases? Martin Ward <martin@gkc.org.uk> - 2020-03-21 19:42 +0000

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