Talk:Classes: Difference between revisions
→The point of the C code?: Some RC-specific perspective
(→The point of the C code?: Some RC-specific perspective) |
|||
| (2 intermediate revisions by 2 users not shown) | |||
Line 82:
Take this with a large grain of salt; this needs to be done carefully to avoid ending up in data type hell. It certainly shouldn't be used recklessly. Like I said, it's not really OOP, just an imitation that allows for some OO design principals to be applied. --[[User:Bnlott|Bnlott]] 00:12, 2 July 2011 (UTC)
::Yes I understand that. It's just sometimes people get too excited and starts abusing some of these techniques. It roughly goes like this, in order:
::# "Oooh let's make the struct inheritable" -- make struct foo "has-a" struct bar and extra members, typecast struct foo* to struct bar*;
::# "Oooh let's make it run-time polymorph" -- add function pointers to struct bar; function looks like method(bar *, ...) but clunky when used on foo; fine, change prototype to method(void *, ...)
::# "But inheritance is not convenient?" -- inplement some kind of vtbl, a global table storing method pointers, while first member of foo and bar refer to this table;
::# "But foo's vtbl and bar's vtbl should not be the same?" -- make foo's vtbl an inherited form of bar's; change the method lookup method--
::Notice how the problem of polymorphism of foo and bar now includes polymorphism of foo and bar's vtbls, and we have a meta recursion, goto 1, sanity lost. It's not pertinent to the code example or your comments, just some amusing observations. --[[User:Ledrug|Ledrug]] 00:34, 2 July 2011 (UTC)
:::As a general rule of thumb, if you ever find yourself implementing half of language B in language A, just go use language B. :) --[[User:Bnlott|Bnlott]] 01:10, 2 July 2011 (UTC)
::::Sure, given reasonable circumstantial constraints. However, just to drop a bit of RC-specific perspective, seeing how to implement language B in language A ''greatly'' makes understanding that half of language B ''much'' easier for someone more versed in language A. Comparing and demonstrating languages is only part of what RC does; demonstrating tasks through code is another major part. --[[User:Short Circuit|Michael Mol]] 04:11, 2 July 2011 (UTC)
| |||