Re: Object Method Call

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Re^2: Object Method Call by AnomalousMonk (Archbishop) on Jul 26, 2009 at 17:39 UTC
... you will notice the problem if you attempt to use $self in display. However, if the call (from within the `test()` subroutine) had been `display($self);` there would have been no problem: this would have emulated the effect of the `->` operator and a `$self->display;` call. This just reinforces moritz and dreadpiratepeter's point that Perl does not know what's in your mind, only in your code.	[reply] [d/l] [select]
Re^3: Object Method Call by Bloodnok (Vicar) on Jul 26, 2009 at 23:53 UTC
How could perl possibly know what's in _my_ mind ... all too frequently, I've absolutely no idea - as I capably demonstrate thro' my rambling postings here :-D Sits back and wonders whether the telepathy engine in perl6 will be more than a figment of someones' fevered imagination ;-\| </silliness> A user level that continues to overstate my experience :-))	[reply]
Re^3: Object Method Call by bkv2k (Novice) on Jul 26, 2009 at 17:44 UTC
Thanks all for the help!	[reply]
Re^3: Object Method Call by afoken (Chancellor) on Jul 27, 2009 at 12:06 UTC
But there is a slightly difference between `display($self)` and `$self->display()`, when a class `XY` inherits from `MyTest` and implements it's own `display()` method. `display($self)` calls `MyTest::display()` even when invoked on an instance of `XY`, whereas `$self->display()` calls `XY::display()` when invoked on an instance of `XY`. So, one could say that `display($self)` breaks inheritance. This is often bad, but sometimes, it can be a useful trick. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]
Re^4: Object Method Call by ikegami (Patriarch) on Jul 27, 2009 at 19:40 UTC
That usually occurs when you're overriding a method, in which case `$self->SUPER::display();` will do the trick.	[reply] [d/l]
Re^5: Object Method Call by afoken (Chancellor) on Jul 27, 2009 at 19:54 UTC
Re^4: Object Method Call by AnomalousMonk (Archbishop) on Jul 27, 2009 at 14:56 UTC
So, one could say that `display($self)` breaks inheritance. It certainly does that if `display` is a method. This is often bad, but sometimes, it can be a useful trick. Hm. Well, I would agree with the word bad, but I think I would delete often unless the goal of the trick is to confuse the heck out of yourself and everyone else. For me, it's hard enough to keep everything in OO programming straight without deliberately trying to trick myself. I'm curious: Can you give an example of how this trick might be productively used?	[reply] [d/l] [select]
Re^5: Object Method Call by afoken (Chancellor) on Jul 27, 2009 at 19:33 UTC
Re^6: Object Method Call by AnomalousMonk (Archbishop) on Jul 28, 2009 at 06:55 UTC


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