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copied!<p>there's no obvious point in doing this. a c style cast is not like other languages - it is a typecast which the address on the left will be identical to the address on the right. cftypes will not throw or return null if you do a bad cast (unlike other languages). iow, it's merely a decoration for you to specify a type, and a c compiler will assume your cast is valid.</p> <p>or perhaps you can provide a better example of how you would use this, if that did not help.</p> <p><strong>Update</strong></p> <p>ok. since you tagged it objc++, i'd just create a helper class which had plenty of diagnostics and did all the noisy conversions (minimal illustration):</p> <pre><code>class t_helper { public: t_helper(CFTypeRef cf) : d_cf(cf), d_type(CFGetTypeID(cf)) { assert(this->d_cf); } ~t_helper() {} /* type info */ bool isString() const { return CFStringGetTypeID() == this->type(); } CFStringRef string() { assert(this->isString()); return this->cf_cast<CFStringRef>(); } bool isDictionary() const { return CFDictionaryGetTypeID() == this->type(); } CFDictionaryRef dictionary() { assert(this->isDictionary()); return this->cf_cast<CFDictionaryRef>(); } ... /* and a trivial example of an operation */ void appendMutableCopyToArray(CFMutableArrayRef array) { if (this->isString()) { CFMutableStringRef cp(CFStringCreateMutableCopy(0,0,this->string())); CFArrayAppendValue(array, cp); CFRelease(cp); } ... } ... private: template < typename T > T cf_cast() { return reinterpret_cast<T>(this->d_cf); } const CFTypeID type() const { return this->d_type; } private: CFTypeRef d_cf; const CFTypeID d_type; }; </code></pre> <p>that's about as accurate as i can get get without a really specific example of the program you are dealing with.</p>

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