Hello Michael,
> It was definitely useful to debug the double/int type stuff within 
> expressions when writing a non trivial pgbench script. It is probably less 
> interesting if there are only integers.
After looking again at the code, I remembered why double are useful: there 
are needed for random exponential & gaussian because the last parameter is 
a double.
I do not care about the sqrt, but double must be allowed to keep that, and 
the randoms are definitely useful for a pgbench script. Now the patch may 
just keep double constants, but it would look awkward, and the doc must 
explain why 1.3 and 1+2 are okay, but not 1.3 + 2.4.
So I'm less keen at removing double expressions, because it removes a key 
feature. If it is a blocker I'll go for just the constant, but this looks 
to me like a stupid compromise.
-- 
Fabien.