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Postings from August 2010
On Thu, Aug 5, 2010 at 5:02 PM, karl williamson <public@khwilliamson.com> wrote: >> * With "use 5.14", the new modifiers may be used either in (?:) or as >> trailing modifiers. Any "run-on" keyword is a syntax error. > > Why forbid using the suffix form in the cases where there is no ambiguity? > That seems wrong to me; it would be quite rare actually for the ambiguity > to arise, so why not (since I'm willing to do the work) make it so that "use > 5.14" essentially just changes to which side any ambiguity resolves? That > doesn't harm pre-existing code, and lets new code get the advantage of the > new modifiers in many more situations than otherwise (almost all, in fact). > We could easily differentiate between a for-certain run-on case and an > ambiguous case, and output different messages. For the ambiguous ones, it > could be something as extensive as "'/regex/le foo' ambiguous; resolved to > '/regex/ le foo'; in 5.16 or in scope of 'use 5.14" will resolve to > '/regex/el foo'" My thought for why not to allow them when there is no ambiguity is to avoid having to explain the special cases. I much prefer something very clean and binary. With "use 5.14" and you get the (trailing) modifiers. Without it, you don't, but can still do them long-hand with (?:). That's really, really easy to explain. And then in 5.16, it all just works. So just because we *can* DWIM in many cases doesn't mean we should. > And what to call the underlying feature? Since it's designed to be > temporary, could its name just begin with an underscore and not be > documented other than that the feature bundle 5.14 includes it? Or would it > be necessary to decouple it from the other features that "use 5.14" enables? My first thought was 'charset_modifiers'. And then for 5.16, it does nothing if turned on and maybe warns if turned off. -- DavidThread Previous | Thread Next