I'm for both of these changes. +1 on the overall idea. On Tue, Jun 19, 2018, 5:58 AM Charles Joynt <charles.jo...@gresearch.co.uk> wrote:
> I'd welcome both of these on the grounds that they'll make life easier > writing short(er) Stellar code AND deciphering what someone else has > written. > > -----Original Message----- > From: Casey Stella [mailto:ceste...@gmail.com] > Sent: 16 June 2018 18:33 > To: dev@metron.apache.org > Subject: Re: [DISCUSS] Treating null as false in boolean expressions in > Stellar > > I created a PR for the empty collection falseyness as well: > https://github.com/apache/metron/pull/1064 so we can choose either of > them if we so desire. > > On Sat, Jun 16, 2018 at 1:10 PM Casey Stella <ceste...@gmail.com> wrote: > > > I created a PR for this functionality, in case we decided for it: > > https://github.com/apache/metron/pull/1063 > > > > Also, while we're talking, perhaps we should treat empty lists as > > false as well, like javascript and python. > > So, for instance, if [] then 'blah' else 'foo' would return foo. > > > > Thoughts? > > > > On Sat, Jun 16, 2018 at 10:17 AM Casey Stella <ceste...@gmail.com> > wrote: > > > >> Right now, because fields may not exist, users can have an awkward time. > >> For instance, checking for is_alert, you end up having to preface > >> checks with exists(is_alert). > >> > >> For instance, in one of our use-cases: > >> https://github.com/apache/metron/tree/master/use-cases/geographic_log > >> in_outliers > >> we use > >> > >> "is_alert := exists(is_alert) && is_alert", "is_alert := is_alert || > >> (geo_outlier != null && geo_outlier == true)", > >> > >> instead of : > >> > >> "is_alert := is_alert || geo_outlier == true", > >> > >> I suggest that we adopt a convention from javascript whereby we > >> assume a field not existing or being null should act as false in > >> boolean expressions. This will simplify stellar's use and hopefully > >> result in less awkwardness. > >> > >> Thoughts? > >> > > > > -------------- > G-RESEARCH believes the information provided herein is reliable. While > every care has been taken to ensure accuracy, the information is furnished > to the recipients with no warranty as to the completeness and accuracy of > its contents and on condition that any errors or omissions shall not be > made the basis of any claim, demand or cause of action. > The information in this email is intended only for the named recipient. > If you are not the intended recipient please notify us immediately and do > not copy, distribute or take action based on this e-mail. > All messages sent to and from this e-mail address will be logged by > G-RESEARCH and are subject to archival storage, monitoring, review and > disclosure. > G-RESEARCH is the trading name of Trenchant Limited, 5th Floor, > Whittington House, 19-30 Alfred Place, London WC1E 7EA. > Trenchant Limited is a company registered in England with company number > 08127121. > -------------- >
