Oct 212014
I am happy to announce that I published a C++ library that offers a lightweight version of a Design by Contract functionality. You can find it under http://github.com/FelixPetriconi/contract_light.
Here is a simple example for the beginning. More to come later
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class Rect { // Use this define if an invariant is defined. If no invariant is defined // no need to do it CONTRACTOR int w_; int h_; public: Rect() : w_(0), h_(0) {} ~Rect() { // checking that the invariants are fulfilled, even before destruction INVARIANT; } void setWidth(int newW) { // setting the pre condition of this method; the invariant is checked // once at the end of the scope PRECONDITION [&] { return newW >= 0; }; // setting the post condition; the invariant is checked only once after // leaving the scope, regardless of the number of pre- and/or post-conditions POSTCONDITION [&, this] { return newW == w_; }; w_ = newW; // There is no need to define here INVARIANT here. This is done automatically // whenever there is a bool invariant() const method is defined } int size() const { int result; POSTCONDITION [&] { return result == w_ * h_; } result = w_ * h_; return result; } bool invariant() const { return w_ >= 0 && h_ >= 0; } }; |