Zhichu Chen wrote:
Hi,
I'm learning to use luatex these days, one day actually. It's very interesting. Although reference manuals are available, I still don't know how to implement my designation.
The thing is, I know there's a "self" variable for object-oriented programming, like ================================================================== \startluacode testdata = { a = 0, b = 0, c = 0, plus = function (self) self.c = self.a + self.b end } mytest = testdata mytest.a=10 mytest.b=100 mytest:plus() tex.print(mytest.c) \stopluacode ================================================================== OK, but what if I wanna do something more, like substract? I would like to use another object, like ================================================================== \startluacode testdata = { a = 0, b = 0, c = 0, calc = Calc } Calc = { plus = function (self) self.c = self.a + self.b end, substract = function (self) self.c = self.a - self.b end } mytest = testdata mytest.a=10 mytest.b=100 mytest.calc:plus() tex.print(mytest.c) \stopluacode ================================================================== Of course this won't work, for the "self" in Calc refers to mytest.calc rather than mytest. How to implement things like that?
Calc = { add = function (self) self.c = self.a + self.b end, substract = function (self) self.c = self.a - self.b end } testdata = { a = 0, b = 0, c = 0, calc = function(self,f) return Calc[f](self) end } mytest = testdata mytest.a=10 mytest.b=100 Calc.add(testdata) print(mytest.c) testdata:calc("substract") print(mytest.c) but it might make more sense to look into metatables (i assume that you own the programming in lua book which explains that) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------