On 09/24/2013 09:03 AM, Laszlo Ersek wrote:
On 09/24/13 10:46, Laine Stump wrote:
On 09/23/2013 08:03 PM, Laszlo Ersek wrote:
... and adapt functions that would cast away the new const qualifier.
Given
typedef virSocketAddr *virSocketAddrPtr;
Compare the parse trees of the following two declarations:
(a) const virSocketAddrPtr addr; (b) const virSocketAddr *addr; Umm.. Eric? A little help? :-) The grammar rules that I used for the AST derivation can be looked up eg. in the final C11 draft,
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf
Section 6.7 "Declarations".
But, the short version is really just that type qualifiers (like const & volatile) don't enter the typedef name; they qualify the variable being declared.
I like your explanation better :-)
In general I disapprove of typedefs: they seem to be friendly by saving you the repeated typing of "struct" and "*". Until they trick you :)
I like typedefs for eliminating repetitive typing of "struct", but not for removing "*" - that seems pointless to me (pun not intended), since you're not saving any characters, and losing track of the nice "*" that everyone is used to seeing.