This is a wrap-up of function cxxfunction in package inline. Additionally, this function returns an object of class cxxdso, which could be saved and reused across R sessions. All arguments except save.dso are passed to function cxxfunction.
is.null.cxxfun
(Package: cxxfunplus) :
Tell if the address of functions created by code{cxxfunction
The function object returned by cxxfunction cannot be saved across R sessions. This function can be used to see if we still have a valid function object. Also this function can be used for functions returned by grab.cxxfun of S4 class cxxdso since these functions are essentially created by cxxfunction or similarly.
The cxxfunction function in inline could not save the dynamic shared objects (DSO) created in a session. We provide a mechanism to save the DSO's if for example, save.image is called.
providing 
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