About constructors of the IntegratorImp class in Chap. 22

[taromori]

Dear Mr./Ms. Cuchulainn,



I am writing to ask you why constructors don't have to be declared in the "IntegratorImp" class in Chap. 22 although an object for this class is constructed in the main function of the "testIntegrator.cpp" file.



This is the same in the inheritated classes such as "TanhRule" and "MidpointRule" classes.



I know this is an elementary question, but I would appreciate it if you make time to answer to the above.



Thanks.