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Is there a difference between copy initialization and direct initialization?

Is there a difference between copy initialization and direct initialization?

Direct initialization behaves like a function call to an overloaded function: The functions, in this case, are the constructors of T (including explicit ones), and the argument is x. Overload resolution will find the best matching constructor, and when needed will do any implicit conversion required.

Which is an example of a second order optimization method?

• Newton’s method is an example of a second order optimization method because it makes use of the curvature or Hessian matrix • Second order methods often converge much more quickly, but it can be very expensive to calculate and store the Hessian matrix.

Can a member of C1 not be initialized?

Any members of c1 that have pod-type (or members of members, etc., etc.) may not be initialized if the user supplied default constructors (if any) do not explicitly initialize them.

When do you use direct initialization in cppreference?

Direct initialization is performed in the following situations: 2) initialization of an object of non-class type with a single brace-enclosed initializer (note: for class types and other uses of braced-init-list, see list-initialization) The effects of direct initialization are: The program is ill-formed

Which is more permissive direct initialization or copy initialization?

Direct-initialization is more permissive than copy-initialization: copy-initialization only considers non- explicit constructors and non-explicit user-defined conversion functions, while direct-initialization considers all constructors and all user-defined conversion functions.

How is an array initialized in cppreference.com?

The array is initialized as in aggregate initialization, except that narrowing conversions are allowed and any elements without an initializer are value-initialized .

Which is the initial value of the object being initialized?

Otherwise, standard conversions are used, if necessary, to convert the value of other to the cv-unqualified version of T, and the initial value of the object being initialized is the (possibly converted) value.