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Re: Creating a calculator

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Op 01-07-16 om 15:52 schreef Steven D'Aprano:
> On Fri, 1 Jul 2016 10:25 pm, Christopher Reimer wrote:
>
>> For my BASIC interpreter, each line of BASIC is broken this way into
>> tokens.
> [...]
>> By using * to unpack the split line, my program no longer crashes and no
>> try/except block is needed to work around the crash. A later line of code
>> will test the expression, ignore if empty or run regex if full.
> I wish you wouldn't describe this as "crash".

I wish you wouldn't mix semantic levels.

>
> The Python interpreter should never crash. That would be a segmentation
> fault, and that is considered to be a very serious bug.

But in that case your computer didn't crash. That would be a your computer
freezing, or rebooting.

>
> But *raising an exception* is another story. Raising exceptions is not a
> crash, it is the interpreter working as expected. This statement:

A segment violation is not a crash either, your computer/os will just
carry on.

>
>     line_number, keyword, expr = "20 END".split(' ', 2)
>
> is SUPPOSED to raise an exception, if it didn't, the interpreter would be
> broken. To call that a "crash" is horribly misleading.

Supposed by whom? The line may be supposed to raise an exception by
the languager designer, that doesn't mean the programmer meant to
write an instruction that would raise an exception. So the programmer
can correctly assert the line was not supposed to raise an exception.

-- 
Antoon.

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Creating a calculator Elizabeth Weiss <cake240@gmail.com> - 2016-06-30 20:08 -0700
  Re: Creating a calculator Michael Torrie <torriem@gmail.com> - 2016-06-30 21:38 -0600
  Re: Creating a calculator DFS <nospam@dfs.com> - 2016-06-30 23:57 -0400
  Re: Creating a calculator DFS <nospam@dfs.com> - 2016-07-01 00:54 -0400
    Re: Creating a calculator Jussi Piitulainen <jussi.piitulainen@helsinki.fi> - 2016-07-01 09:42 +0300
      Re: Creating a calculator Christopher Reimer <christopher_reimer@icloud.com> - 2016-07-01 05:25 -0700
        Re: Creating a calculator Jussi Piitulainen <jussi.piitulainen@helsinki.fi> - 2016-07-01 15:46 +0300
          Re: Creating a calculator Christopher Reimer <christopher_reimer@icloud.com> - 2016-07-01 06:19 -0700
            Re: Creating a calculator Jussi Piitulainen <jussi.piitulainen@helsinki.fi> - 2016-07-01 16:35 +0300
        Re: Creating a calculator Steven D'Aprano <steve@pearwood.info> - 2016-07-01 23:52 +1000
          Re: Creating a calculator alister <alister.ware@ntlworld.com> - 2016-07-01 14:21 +0000
          Re: Creating a calculator Christopher Reimer <christopher_reimer@icloud.com> - 2016-07-01 07:15 -0700
          Re: Creating a calculator Jussi Piitulainen <jussi.piitulainen@helsinki.fi> - 2016-07-01 20:44 +0300
          Re: Creating a calculator Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2016-07-04 12:32 +0200
      Re: Creating a calculator DFS <nospam@dfs.com> - 2016-07-01 20:16 -0400
    Re: Creating a calculator pdorange@pas-de-pub-merci.mac.com (Pierre-Alain Dorange) - 2016-07-01 11:34 +0200
      Re: Creating a calculator Chris Warrick <kwpolska@gmail.com> - 2016-07-01 13:39 +0200
        Re: Creating a calculator pdorange@pas-de-pub-merci.mac.com (Pierre-Alain Dorange) - 2016-07-01 15:03 +0200
      Re: Creating a calculator DFS <nospam@dfs.com> - 2016-07-01 20:16 -0400
        Re: Creating a calculator pdorange@pas-de-pub-merci.mac.com (Pierre-Alain Dorange) - 2016-07-04 11:50 +0200
        Re: Creating a calculator BartC <bc@freeuk.com> - 2016-07-06 01:53 +0100
          Re: Creating a calculator Quivis <quivis@domain.invalid> - 2016-07-07 22:00 +0000
  Re: Creating a calculator Chris Warrick <kwpolska@gmail.com> - 2016-07-01 10:57 +0200

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