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Postings from December 1999
Tim Bunce <Tim.Bunce@ig.co.uk> writes: >On Mon, Dec 20, 1999 at 02:10:54PM +0000, Nick Ing-Simmons wrote: >> >> While debugging SV leakage in Tk I noticed that when GVs are dropped >> into derived class package to represent the "inherited" methods >> the GVs have their SV slot filled in with a NULL SV. >> >> Is this either necessary or useful? >> When you have a system like Tk with lots of inherited methods >> having $Tk::Text::destroy created when you call $text->destroy >> means quite a few SVs get called into being never to be used. > >I recall Larry saying that all GVs get an SV for free. Hmm, that is a strange sense of 'free' - all GVs are taxed by one SV ;-) The mandatory SV is indeed there in gv_init(). This means I have $ISA $STDOUT $_/usr/local/lib/perl5/base.pm and all kinds of such garbage. This was presumably to avoid the extra test so that GvSV was quicker than GvAVn - but this is of less value now that "most" scalar vars are presumed to be lexical. >Maybe that's no longer the win it as presumed to be. > >Tim. -- Nick Ing-Simmons <nik@tiuk.ti.com> Via, but not speaking for: Texas Instruments Ltd.