Re: [Libreoffice] semantics of ScBaseCell* lclCloneCell
On 10/27/2011 07:10 AM, Kevin Hunter wrote: I'm nosing around ScBaseCell in sc/source/core/data/cell.cxx, and I'm curious about the semantics of the function lclCloneCell. Specifically, when would that function ever return a NULL pointer? Does Calc not know about all its cell types? Perhaps extensions are able to add their own cell types and still use this function? (Then why would they use this function?!) Not an sc expert, but from looking at the code it looks to me like the default case shall never be reached, but is there to (a) silence compiler warnings and (b) fire an OSL_FAIL in case there is a programming error that causes the case to be reached nonetheless (I usually put a this cannot happen into such OSL_FAILs, in good old Knuth tradition). And since the function still needs to syntactically return something, even in this unreachable case, it returns the canonic null value. Stephan ___ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
Re: [Libreoffice] semantics of ScBaseCell* lclCloneCell
Hi Stephan, On Thursday, 2011-10-27 08:49:19 +0200, Stephan Bergmann wrote: On 10/27/2011 07:10 AM, Kevin Hunter wrote: I'm nosing around ScBaseCell in sc/source/core/data/cell.cxx, and I'm curious about the semantics of the function lclCloneCell. Not an sc expert Perfect analysis nonetheless ;) Eike -- LibreOffice Calc developer. Number formatter stricken i18n transpositionizer. GnuPG key 0x293C05FD : 997A 4C60 CE41 0149 0DB3 9E96 2F1A D073 293C 05FD pgpOtrradalW0.pgp Description: PGP signature ___ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
Re: [Libreoffice] semantics of ScBaseCell* lclCloneCell
At 2:49am -0400 Thu, 27 Oct 2011, Stephan Bergmann wrote: On 10/27/2011 07:10 AM, Kevin Hunter wrote: I'm nosing around ScBaseCell in sc/source/core/data/cell.cxx, and I'm curious about the semantics of the function lclCloneCell. Specifically, when would that function ever return a NULL pointer? Does Calc not know about all its cell types? Perhaps extensions are able to add their own cell types and still use this function? (Then why would they use this function?!) Not an sc expert, but from looking at the code it looks to me like the default case shall never be reached, but is there to (a) silence compiler warnings and (b) fire an OSL_FAIL in case there is a programming error that causes the case to be reached nonetheless (I usually put a this cannot happen into such OSL_FAILs, in good old Knuth tradition). And since the function still needs to syntactically return something, even in this unreachable case, it returns the canonic null value. Huh. Then why use a switch? Why not use an if-else set of clauses? I recognize that this function may be called a lot, but does an if vs switch statement mean /that/ much in terms of performance? In any event, thanks for the response. Kevin ___ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
[Libreoffice] semantics of ScBaseCell* lclCloneCell
Hullo Calc Devs, I'm nosing around ScBaseCell in sc/source/core/data/cell.cxx, and I'm curious about the semantics of the function lclCloneCell. Specifically, when would that function ever return a NULL pointer? Does Calc not know about all its cell types? Perhaps extensions are able to add their own cell types and still use this function? (Then why would they use this function?!) Thanks, Kevin ___ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
