Package 'cxxfunplus'

cxxfunplus: save the dynamic shared objects (DSO) for cxxfunction

Description

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.

Details

Instead of calling cxxfunction in inline, call cxxfunctionplus in this package, from which an S4 class of cxxdso is returned. We could use generic function grab.cxxfun of class cxxdso to retrieve the functions typically returned by cxxfunction.

Author(s)

Jiqiang Guo <[email protected]>

Maintainer: Jiqiang Guo <[email protected]>

See Also

cxxfunctionplus, inline

---

Class "cxxdso"

Description

An S4 class for saving the dynamic shared objects created on the fly

Objects from the Class

Objects can be created by calls of cxxfunctionplus.

Slots

sig:

Object of class "list" The signatures of functions defined.

dso_saved:

Object of class "logical" Whether to save the DSO or not.

dso_filename:

Object of class "character" The original file name for the DSO when it is created (no extension).

system:

The operating system where the object is created.

.MISC:

Object of class "environment" An environment to save the functions returned by cxxfunction with name cxxfun, the last full path for the DSO with name dso_last_path, and the vector of raw for saving the binary dynamic shared object (DSO) with name dso_bin.

Methods

show

signature(x = "cxxdso"): Print a summary of the object.

grab_cxxfun

signature(object = "cxxdso"): Return the function objects contained.

is_dso_loaded

signature(object = "cxxdso"): Tell if the DSO (DLL) is loaded.

getDynLib

signature(x = "cxxdso"): Obtain the DLL associated.

See Also

getDynLib, grab_cxxfun, and cxxfunctionplus

Examples

showClass("cxxdso")

---

To created an S4 class cxxdso from C++ code

Description

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.

Usage

cxxfunctionplus(sig = character(), body = character(), 
                plugin = "default", includes = "", 
                settings = getPlugin(plugin), 
                save_dso = FALSE, ..., verbose = FALSE)

Arguments

sig	Signature of the function. A named character vector.
body	A character vector with C++ code to include in the body of the compiled C++ function.
plugin	Name of the plugin to use. See getPlugin for details about plugins.
includes	User includes, inserted after the includes provided by the plugin.
settings	Result of the call to the plugin.
save_dso	Determine whether to save the compiled code (DSO); defaults to FALSE.
...	Further arguments to the plugin.
verbose	verbose output.

Value

An object of S4 class cxxdso.

See Also

cxxfunction and cxxdso

Examples

## Not run: 
src <-  ' return ScalarReal(INTEGER(x)[0] * REAL(y)[0]);'
dso <- cxxfunctionplus(signature(x = "integer", y = "numeric"), src)
show(dso)

## End(Not run)

---

Retrieve the dynamic library (or DLL) associated with an object of class cxxdso

Description

The getDynLib function retrieves the dynamic library (or DLL) associated with objects of class cxxdso generated by cxxfunctionplus

Methods

signature(x = "cxxdso")

Retrieves the dynamic library associated with the cxxdso objects generated by cxxfunctionplus.

See Also

getLoadedDLLs, dyn.load, cxxdso, and getDynLib in inline

Examples

## Not run: 
dso <- cxxfunctionplus(signature(), "return R_NilValue;")
dll <- getDynLib(dso)

## End(Not run)

---

Retrieve the functions object associated with an object of class cxxdso

Description

The grab_cxxfun function retrieves the function object associated with objects of class cxxdso generated by cxxfunctionplus

Methods

signature(x = "cxxdso")

Retrieves the function object associated with the cxxdso objects generated by cxxfunctionplus.

See Also

cxxfunctionplus, cxxdso

Examples

## Not run: 
dso <- cxxfunctionplus(signature(), "return R_NilValue;")
fx <- grab_cxxfun(dso)
fx()

## End(Not run)

---

Tell if a cxxdso object is loaded

Description

The is_dso_loaded function tell if the dynamic shared object (DSO, or DLL) in an object of cxxdso, created by function cxxfunctionplus, is loaded.

Methods

signature(x = "cxxdso")

Tell if a cxxdso object is loaded in the sense that the contained DSO is loaded or not.

See Also

cxxdso

Examples

## Not run: 
dso <- cxxfunctionplus(signature(), "return R_NilValue ;")
print(is_dso_loaded(dso))

## End(Not run)

---

Tell if the address of functions created by cxxfunction points to NULL

Description

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.

Usage

is_null_cxxfun(cx)

Arguments

cx	A function of class CFunc

Details

R could not save the function objects that point to dynamically loaded functions, especially for those function created on the fly using package inline at least for one reason that those DSO's are deleted after quitting R. So it is always safe to tell if it is valid before call functions created by cxxfunction.

Value

Logical: TRUE null pointer; FALSE, not null, this function can still be called.

See Also

cxxfunction

---