On Sat, Jan 10, 2015 at 11:02 PM, Moritz Lenz <mor...@faui2k3.org> wrote:
> To elaborate a bit on the previous answer: > > On 10.01.2015 17:12, Tobias Leich wrote: > >> In case we would know that certain methods had no side effects (and are >> not called because of their side effects), ... >> >> But at the moment we don't know and therefore we can't warn for every >> method. >> > > there are two possible choices for warnings: run time and compile time. > > Run-time warnings suffer from run-time overhead, and I think this would be > unacceptable here. > > Compile-time warnings can't work here, because at compile time we don't > know what method we'll dispatch to eventually. Note that subroutine calls > already have such warnings (in some cases): > > $ perl6-m -e 'sqrt(4); say "done"' > WARNINGS: > Useless use of "sqrt(4)" in expression "sqrt(4)" in sink context (line 1) > done > > Oh right. Multiple dispatch. I see. anyway, IMHO the run-time overhead would be probably ok if it was optional. Like a development mode. It would certainly be faster than people, especially beginners like me, wasting their time not understanding why the method does not have an impact on that object. Gabor
