April 21, 2007 Access violation in trying to use a class | ||||
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I have written following code: --------------------------- import std.stdio; class Abc { public: int add(int a, int b) { return a + b; } } void main() { Abc abc; int a = abc.add(1, 2); } ---------------------------- Upon compilling and building I executed a program. The message appeared: "Error: Access Violation". What should I do to use classes? |
April 21, 2007 Re: Access violation in trying to use a class | ||||
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Posted in reply to Niovol | On Sat, 21 Apr 2007 12:46:14 +0000 (UTC), Niovol wrote: > I have written following code: > --------------------------- > import std.stdio; > class Abc > { > public: > int add(int a, int b) { return a + b; } > } > void main() > { > Abc abc; > int a = abc.add(1, 2); > } > ---------------------------- > Upon compilling and building I executed a program. The message appeared: "Error: Access Violation". What should I do to use classes? Firstly, this newsgroup is o longer active. Please use the group "digitalmars.D" next time. But back to your problem. Unlike C++, D requires that all classes be instantiated before use. That means, you must use a 'new' statement on your object before trying to access it. In D, a simple declaration such as your Abc abc; only allocates space for a null reference. This should work ... import std.stdio; class Abc { public: int add(int a, int b) { return a + b; } } void main() { Abc abc = new Abc; // Must be instantiated before use. int a = abc.add(1, 2); Abc def; int b; def = new Abc; // 'new' before use. b = abc.add(3, 4); } -- Derek Parnell Melbourne, Australia "Justice for David Hicks!" skype: derek.j.parnell |
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