Basic question in C/ C++

[Javagal Srinath]

Hi I have a theoritical doubt in c/c++, that at the end of some functions I am seeing a const keyword. I dont know what is the purpose behind this. for example int function(int funcpar1,int funcpar2)const; I want to know purpose of the const keyword at the end Thanks

[Viorel]

This means that the function does not modify data members of the class and does not call other functions which are not marked as const. Functions that just read and return information must be made const. Otherwise the following sample will not work:

const CMyString s = "Test";
int length = s.GetLength(); // Does not work if GetLength function is not marked as const

This is because the s variable was declared as constant, se we cannot modify it. -- modified at 6:33 Friday 30th June, 2006

[Kevin McFarlane]

Have a read of the "Methods" section here under C++ syntax: http://en.wikipedia.org/wiki/Const_correctness[^] Also see the links at the bottom. Kevin

[Sarath C]

In those const functions, we could not change an object's state (be more specific member variables value) examples are some "Get" interfaces, those function's (most probably) are not supposed to change it's object state, it is for returning something that belong to the object. Putting const at end of function meaningfully is a good practice. SaRath.
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