typedef name question

Daniel Lohmann daniel.lohmann@informatik.uni-erlangen.de
Mon Jan 29 16:16:00 GMT 2007


Hi Michal,

John (Eljay) Love-Jensen wrote:
 > You are allowed to introduce identifiers in a scope that
 > shadow identifiers outside that scope.  Even in the
 > "foo foo;" case, where you are using an outer scope
 > identifier and in the process are introducing a new
 > identifier that shadows that self-same outer
 > scope identifier.

Just a small add-on:

In C++ you can easily test this rule and still access the outer identifier 
by explicitly looking it up in global namespace scope. The following 
compiles with g++:

// foo is defined in the global namespace
typedef int foo;

foo foo_fct(int a) {
    foo foo;              /* line 3: a variable foo with type foo */
    return (::foo)foo;    /* line 4: cast to outer foo */
}


Of course, this does not work with C.

Daniel



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