C
++
Primer, Fifth Edition
Workarounds for C
++
11 Features
not Implemented in Visual Studio 2012
Barbara E. Moo
bmoo@att.net
August 9, 2012
Some C
++
11 features used in C
++
Primer are not yet implemented in the
latest Microsoft compiler (Visual Studio 2012). This document outlines these
unimplemented features and, where possible, suggests workarounds.
We used the release candidate, Version 17.00.50522.1, to test the code that
is included on the book’s website. When Visual Studio is generally available
(expected to be sometime in mid-September)wewillverifythecodeandmake
any updates as appropriate.
constexpr variables Use const instead. Note, the compiler will not verify
that the initializer is a constant expression.
constexpr functions Explicitly write out the code that would have been in-
side the function. Note, preprocessor macros are a reasonable substitute for
constexpr functions. However, as with const variables, the compiler will
not verify whether the macro returns a constant expression.
constexpr constructors and member functions There is no workaround.
= default Explicitly define the member. Because the compiler does not yet
implement in-class initializers, it is important to remember that the default
constructor should explicitly initialize every member of built-in type.
= delete For a member function, declare the member as private and do
not supply a definition for that member.
Delegating and inherited constructors Write the corresponding definitions di-
rectly.
func Use the Microsoft nonstandard CPP variable, FUNCTION ,which,
like
func , holds the name of the current function.
Using function with pointers to member There is a known bug that causes
the compiler to incorrectly reject some uses of pointers to members with the
library function template. Use mem_fn to generate a callable object. For
example, assuming that Lshift is a member of a class named ShiftOps:
// compiler incorrectly rejects this code
function<int (ShiftOps
*
, int, int)> memp =
&ShiftOps::Lshift;
// equivalent code that does compile
function<int (ShiftOps
*
, int, int)> memp =
mem_fn(&ShiftOps::Lshift);
In-class initializers Explicitly supply the initializer in the constructor initial-
izer list of every constructor that would otherwise use the in-class initializer.
Doing so is particularly important for members of built-in type.
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