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To: python-list@python.org
From: Ned Batchelder <ned@nedbatchelder.com>
Subject: Re: Experiences/guidance on teaching Python as a first programming language
Date: Fri, 20 Dec 2013 21:04:24 -0500
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On 12/20/13 6:58 PM, Dennis Lee Bieber wrote:
> On 20 Dec 2013 02:16:05 GMT, Steven D'Aprano
> <steve+comp.lang.python@pearwood.info> declaimed the following:
>
>>
>> 2) Even for kernel developers, I believe that systems languages should be
>> safe by default. You ought to have to explicitly disable (say) bounds
>> checking in critical sections of code, rather than explicitly enable it.
>> Or worse, have to program your own bounds checking -- especially if the
>> compiler is permitted to silently disregard it if you make one tiny
>> mistake.
>>
> 	I wonder how BLISS falls into that... Have to read the rest of
> http://en.wikipedia.org/wiki/BLISS (while I had 22 years on VMS, it was
> mostly F77, a touch of F90, C, Pascal, and some DCL; but never used BLISS)
>

Bliss is even lower-level than C.  It made the too-consistent choice of 
having names mean the same thing on the left-hand side of an assignment 
as on the right-hand side.  A name meant the address of a variable, so 
to access the value of a variable, you had to dereference it with the 
dot operator, much like the unary asterisk in C.

C:	a = b
Bliss:	a = .b

C:	a = a + 1
Bliss:	a = .a + 1

C:	a = *b
Bliss:	a = ..b

C: 	a = &b
Bliss:	a = b

It was far too common to forget the dots...

-- 
Ned Batchelder, http://nedbatchelder.com