digitalmars.D.learn - How can I store delegates in array?
- Chopin (30/30) Nov 30 2012 Hi!
- H. S. Teoh (8/11) Nov 30 2012 [...]
- Chopin (42/42) Nov 30 2012 I tried the following:
- H. S. Teoh (13/54) Nov 30 2012 [...]
- Chopin (1/1) Nov 30 2012 Amazing! It works! Thank you so much :)
Hi! I've never used delegates before etc. not really familiar with it. I was trying something like this: import std.stdio; import std.regex; bool lol(string name, string val) { if (name == "lal") if (val[0..3] == "2124") return true; return false; } bool lal(string name, string val) { return false; } void main() { struct Filter { private bool delegate(string, string)[] delFuncs; // array with functions :D public void add(bool delegate(string, string) filter_func) { delFuncs ~= filter_func; } } auto x = Filter(); x.add(&lol); x.add(&lal); writeln(x); } How can I make this work? Thank you :)
Nov 30 2012
On Fri, Nov 30, 2012 at 04:41:40PM +0100, Chopin wrote:Hi! I've never used delegates before etc. not really familiar with it.[...] You could try something like this: alias bool delegate(string, string) DgType; DgType[] arrayOfDelegates; T -- Why waste time learning, when ignorance is instantaneous? -- Hobbes, from Calvin & Hobbes
Nov 30 2012
I tried the following: import std.stdio; import std.regex; bool lol(string name, string val) { if (name == "lal") if (val[0..3] == "2124") return true; return false; } bool lal(string name, string val) { return false; } alias bool delegate(string, string) DgType; void main() { struct Filter { private DgType[] delFuncs; // array with functions :D public void add(DgType filter_func) { delFuncs ~= filter_func; } } auto x = Filter(); x.add(&lol); x.add(&lal); writeln(x); } Didn't work... just a bunch of errors... t.d(28): Error: function t.main.Filter.add (bool delegate(string, string) filter_func) is not callable using argument types (bool function(string name, string v al)) t.d(28): Error: cannot implicitly convert expression (& lol) of type bool function(string name, string val) to bool delegate(string, string) t.d(29): Error: function t.main.Filter.add (bool delegate(string, string) filter_func) is not callable using argument types (bool function(string name, string v al)) t.d(29): Error: cannot implicitly convert expression (& lal) of type bool function(string name, string val) to bool delegate(string, string) Thanks for help!
Nov 30 2012
On Fri, Nov 30, 2012 at 04:57:44PM +0100, Chopin wrote:I tried the following: import std.stdio; import std.regex; bool lol(string name, string val) { if (name == "lal") if (val[0..3] == "2124") return true; return false; } bool lal(string name, string val) { return false; } alias bool delegate(string, string) DgType; void main() { struct Filter { private DgType[] delFuncs; // array with functions :D public void add(DgType filter_func) { delFuncs ~= filter_func; } } auto x = Filter(); x.add(&lol); x.add(&lal); writeln(x); } Didn't work... just a bunch of errors... t.d(28): Error: function t.main.Filter.add (bool delegate(string, string) filter_func) is not callable using argument types (bool function(string name, string v al))[...] Ah, I see the problem. What you want are *function pointers*, not delegates. So do this instead: alias bool function(string,string) FuncType; struct Filter { private FuncType[] delFuncs; ... } T -- Prosperity breeds contempt, and poverty breeds consent. -- Suck.com
Nov 30 2012