Is a type specifier required here?
const c = 7;
Bjarne Stroustrup's 'The C++ Programming Language' on page 80 says that this is illegal. However, I've been practicing some brainbench tests, and one of the questions states that the type defaults to int. Brainbench is usually correct, so I'm unsure of which reference is right, and I've been unable to find anything in the standard. Does anyone have a definitive answer and a reference?
The default type of int is valid for C, but not for C++. Even in C this style of coding should be avoided. Also note that Bjarne Stroustrup's book is one of the most authoritative reference for standard C++.
I can't speak to the standard... but just looking at a statement like const c = 7; screams bad code style to me. As far as compiler compatibility... it's probably going to be hit-and-miss. Microsoft Visual Studio's compiler won't have any part of it when compiling a C++ file (.cpp extension) but doesn't choke on it when compiling a C file (.c extension) mainly because the C standard allows for defaulting variables as int when no type is specified.
For C++ I would believe Stroustrup over any place but a standard.
Perhaps the question was about C not C++?
The draft C++0x standard in section 7.1.6 says
At least one type-specifier that is not a cv-qualifier is required in a declaration unless it declares a constructor, destructor or conversion function.83 A type-specifier-seq shall not define a class or enumeration unless it appears in the type-id of an alias-declaration (7.1.3).