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Postings from May 2008
Glenn Linderman skribis 2008-05-21 8:50 (-0700): > On approximately 5/21/2008 1:29 AM, came the following characters from > the keyboard of Rafael Garcia-Suarez: > >Some way to mark PVs as "binary" and not upgradeable to SvUTF8 would be > >handy, though. > What's the goal? Dual: 1. To provide a means of indicating that something is binary rather than text. This can be useful in an encoding capable DBI drivers/wrappers for example, to indicate that a "?" placeholder is already binary, and should not be text-encoded. (You'd want to do this based on column introspection but that's very slow and very hard to write portably.) Another use case involves data serialization for exchange with languages that have native binary strings, like Java. 2. To prevent programming errors; you should see this as a matter of strictures. Most silly mistakes made in Unicode programming are related to people who fail to understand the difference between binary and text strings, and as a result from that, they sometimes add text strings to binary strings. While conceptually that's always a mistake, it happens so often and it's such an easy mistake te make (apparently) that it would be nice to have language support that changes "upgrade entire string to SvUTF8" to "add only the new portion as UTF8 (encoded, not SvUTF8 marked), keep the original as it is" > If the goal is to prevent the cost of upgrading and downgrading, well, > just fix the bug that attached the upgraded data... and the cost of > doing so also vanishes. Detecting upgrades is hard. There's a module (encoding::warnings) that enables warnings for it globally, but you often want it on a single string instead. Indeed the bug where characters >255 are added to the binary string should be fixed, but finding out where/when that happens can be a lot of work and currently requires knowledge of internals. -- Met vriendelijke groet, Kind regards, Korajn salutojn, Juerd Waalboer: Perl hacker <#####@juerd.nl> <http://juerd.nl/sig> Convolution: ICT solutions and consultancy <sales@convolution.nl> 1;