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I have a function: Task<Result> GetSomething(string params) { var website = getWeb(params); if (website.StatusCode != HttpStatusCode.OK) { //do something } else { return website } } I have some solutions to deal with error: return null return a tuple with the result and a bool indicates if successful or not, like return (null, false); andRead more

I have this ctuple class, the unit tests compile and work as expected with constexpr qualifiers, my issue is that it is only valid for default constructible types. Any suggestions and advice is appreciated. #pragma once #include <type_traits> #include <utility> template<size_t Index, typename… Ts> struct ct_select; template<typename T, typename… Ts> struct ct_select<0, T, Ts…> {Read more

I’m having a problem translating the following to tuple relational calculus. the db is: Employee(eid,ename,salary,did,classification) Project(pid,pname,did,budget,ddate) Department(did,dname,floor,head) dbudget(did,byear,budget) Project(pid,pname,did,budget,ddate) Onproject(pid,eid,fdate) i’m having a problem creating a tuple relational expression for those 2 cases: 1)show projects that their due date is not yet passed(Project.ddate), and that all of the employees on that project belong to aRead more

The specific example in mind is a list of filenames and their sizes. I can’t decide whether each item in the list should be of the form {“filename”: “blabla”, “size”: 123}, or just (“blabla”, 123). A dictionary seems more logical to me because to access the size, for example, file[“size”] is more explanatory than file[1]…Read more

Suppose this state for the relation schema Company I’m stuck trying to understand how, why and when I should use Quantifiers (Existencial and Universal) Examples: Here I understand how the existencial is working, all the formula bounded to him would evaluate to TRUE, if at least one of all the possible tuples that d canRead more