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Re: Applesoft limitation



mojoehand wrote:
I haven't done anything with Applesoft in many years. I was just
trying to do something simple and re-learned that Applesoft doesn't
have things that I am used to having in other BASICs. In particular, I
needed the INSTR() function, but it's not there. Short of using
another BASIC or even another language, is there some "enhancement"
software to add INSTR() and such to Applesoft? Or, is there any way to
fake this function in standard Applesoft?

I've learned to try not to "need" this function.  ;-)

When it cannot be avoided, you have at least three choices:

1. Assembly code (there are almost certainly some INSTR ampersand
   or USR commands out there...)

2. Direct implementation in Applesoft using MID$--not hard, but
   pretty slow (OK if you don't use it too often).

3. An intermediate approach using the DATA statement scanner to
   collect "tokens" for comparison and use.

The third approach is several times faster than 2), but still
quite slow compared to 1).  My File Server for NadaNet uses
this approach to do lexical scanning of request strings:

http://home.comcast.net/~MJMahon/FileServer.html

-michael

******** Note new website URL ********

NadaNet and AppleCrate II for Apple II parallel computing!
Home page:  http://home.comcast.net/~mjmahon/

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