> On 6 Aug 2018, at 12:38 am, Mark Waddingham via use-livecode
> <use-livecode@lists.runrev.com> wrote:
>
> keeping where P -> P
> keeping with P -> each matches wildcard P
> keeping without P -> not (each matches wildcard P)
> keeping matching P -> each matches pattern P
> keeping not matching P -> not (each matches wildcard P)
>
> discarding where P -> not P
> discarding with P -> not (each matches wildcard P)
> discarding without P -> each matches wildcard P
> discarding matching P -> not (each matches pattern P)
> discarding not matching P -> each matches wildcard P
>
> So the actual underling operation is the same: P is a boolean predicate
> operating on 'each', where each is taken to be each 'chunk' of X in turn; if
> P(each) returns true, the element is kept, otherwise it is discarded.
>
> I quite like the above - it has a very simple underbelly (a single
> operation!), but the actual English-like syntax is a true and correct
> sentence.
>
> What do people think?
I think it’s nice sugar but it adds complexity when trying to understand the
statement. You need to comprehend the expression or pattern then comprehend the
relationship between discarding/keeping and with | without | not matching |
where in order to figure out what will actually happen. I would rather [by {
keeping | discarding }] be a parser error if used with without and not matching.
Cheers
Monte
_______________________________________________
use-livecode mailing list
use-livecode@lists.runrev.com
Please visit this url to subscribe, unsubscribe and manage your subscription
preferences:
http://lists.runrev.com/mailman/listinfo/use-livecode
