In response to a message written on 02.10.2014 01:26, from Wayne Stambaugh: > On 10/1/2014 3:08 PM, jp charras wrote: >> Le 01/10/2014 20:42, Daniel Dawid Majewski a écrit : >>> On 01.10.2014 16:25, Wayne Stambaugh wrote: >>>> They do. It is automatically generated by the compiler just like the >>>> source code comment explains. Unless you need some special copy >>>> semantics (not just a direct copy of every class member which is what >>>> the compiler will generate), you do not need to write your own copy >>>> constructor. >>> Ok, so where are nested following python methods ?: >>> Copy(MODULE self, MODULE src) >>> Copy(ZONE_CONTAINER self, ZONE_CONTAINER src) >>> How I could make ?: >>> Copy(TRACK self, TRACK src) >>> Copy(VIA self, VIA src) >> >> Seems there is a mistake between a copy constructor and the Copy method >> which exists for some BOARD_ITEMS, but not all (because currently this >> method is not needed in C++ Kicad code for track/vias) >> >> The Copy method copy only some values from an existing source to an >> existing target. >> >> The default copy constructor creates a clone (a new item) of an item. >> This is very different. >> >> I'll add a Copy method (mainly for python scripts) for tracks/vias soon. > > Please don't unless there is no other solution. There is no reason to > create a custom copy method when the default copy constructor is more > reliable. I promise you someone will add another class member that they > will forget to add to the copy method. We've been bit by this several > times in the past. It's a poor design pattern that I do not want to > repeat. The only time I can think of the use a custom copy constructor > is when dynamically allocated memory is involved. Are we using copyctor > feature flag in SWIG when generating the C++ source files? If not, then > an explicit copy constructor must be defined. You can read about it > here http://www.swig.org/Doc1.3/SWIGPlus.html#SWIGPlus_nn7. Let see if > we can get SWIG to do it for us before we travel down the bad design path. IMHO JP Charas is not going to do with any coping class. That's misunderstanding. I suggest to rename all python „Copy” methods to „paramCopy”(or sth similar), cause in fact they are only coping values of elements between instances of same class. Python formula „newItem = Item.__class__(pcb)” makes new instance of the same class, so we no need class copy or sth similar… Apart from this, we have python method „Clone”, which seems unusable - returns some bogus instance of pcbnew.EDA_ITEM. It's possible to make it workable by overloading method with creating new instance of the same class [Item.__class__(pcb)] and then coping values from old to new instance.
-- Best Regards, LordBlick _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
