Re: extend pgbench expressions with functions

>> Thanks.  Part 1 looks, on the whole, fine to me, although I think the
>> changes to use less whitespace and removing decimal places in the
>> documentation are going in the wrong direction.  That is:
>> 
>> -      About 67% of values are drawn from the middle <literal>1.0 / 
>> threshold</>
>> +      About 67% of values are drawn from the middle <literal>1/param</>,
>> 
>> I would say 1.0 / param, just as we used to say 1.0 / threshold.  Any
>> reason why not?
>
> For the 1.0 -> 1, this because in the example afterwards I set param to 2.0 
> and I wanted it clear where the one half was coming from, and ISTM that the 
> 2.0 stands out more with "1 / 2.0" than with "1.0 / 2.0".
>
> For the spaces, this is because with just "1/" the space seemed less 
> necessary for clarity, but it seemed necessary with "1.0 /"
>
> Now it is easy to backtrack.

After looking at the generated html version, I find that the "1/param" and 
"2/param" formula are very simple and pretty easy to read, and they would 
not be really enhanced with additional spacing.

ISTM that adaptative spacing (no spacing for level 1 operations, some for 
higher level) is a good approach for readability, ie:
   f(i) - f(i+1)             ^ no spacing here        ^ some spacing here

So I would suggest to keep the submitted version, unless this is a 
blocker.

-- 
Fabien.