Re: Is perl still the No.1 language for sysadmin?
davidson wrote:
> On Sat, 8 Apr 2023 Emanuel Berg wrote:
>
>> Tom Dial wrote:
>>
>>>>> Look at the use of parentheses in Lisp [...]
>>>>
>>>> I have thought about that - is Lisp possible without them?
>>>> But how do you then know priority? I'm sure someone tried
>>>> to get rid of them, but how?
>>>
>>> Its quite a few years since I had anything to do with Lisp,
>>> and even more since I wrote my Symbolic Logic final using
>>> parenthesis-free Polish notation (i.e., Reversed RPN).
>>
>> Yes, you mean instead of
>>
>> (* 1 2 (+ 1 2 3) 3)
>>
>> How would that look?
>
> That particular term, with those commutative operators (in
> *Reversed* Reverse Polish Notation, ie, in Polish/Prefix
> Notation), is equivalent to this:
>
> * 1 2 3 + 1 2 3
? Not following ...
> In the general case, allowing operators of variable arity
> (which I doubt were part of the logic exam) require an
> arity-indicating argument, but that's simple enough,
> isn't it?
>
> So your example, without commutation of the arguments, would be
>
> *4 1 2 +3 1 2 3 3
>
> with *4 indicating 4-nary multiplication, and +3
> ternary addition.
No can't have that, what if you don't know the arity (it's
computed) and no new goofy syntax introduced haha :)
--
underground experts united
https://dataswamp.org/~incal
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