[erlang-questions] Reading, Learning, Confused

[Edwin Fine]

I cannot imagine of any situation where or and orelse work the same and
reinstalling changes that. Please could you paste your exact code and shell
session, showing the problem? Also, which version of Erlang are you using?

On Sat, Jul 19, 2008 at 10:51 AM, Sean Allen <sean@REDACTED>
wrote:

>
> On Jul 19, 2008, at 10:47 AM, Edwin Fine wrote:
>
>  You are getting twisted in knots.
>>
>> 1> X =0.
>> 0
>> 2> (X == 0) orelse (1/X > 2).
>> true
>> 3> f().
>> ok
>> 4> X = 1.
>> 1
>> 5> (X == 0) orelse (1/X > 2).
>> false
>> 8> f().
>> 9> X = 0.
>> 0
>> 10> (X == 0) or (1/X > 2).
>> ** exception error: bad argument in an arithmetic expression
>>     in operator  '/'/2
>>        called as 1 / 0
>>
>> So the orelse construct works as advertised. It will not evaluate any
>> expressions after the first false condition and prevents divide by zero.
>>
>
> i need to reinstall because orelse doesnt for me. it works the exact same
> or.
>
> but assuming i get a working install the reason in the example that or
> fails is because of the divide by zero correct?
>
> which raises a new question...
>
> why does or evaluate all the conditions? what purpose does that serve? when
> would you use or instead of orelse?
>
>
>


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