is.function Is an Object of Type (Primitive) Function?
 Description
Checks whether its argument is a (primitive) function.
Usage
is.function(x) is.primitive(x)
Arguments
| x | an R object. | 
Details
is.primitive(x) tests if x is a primitive function, i.e, if typeof(x) is either "builtin" or "special". 
Value
TRUE if x is a (primitive) function, and FALSE otherwise. 
Examples
is.function(1) # FALSE is.function (is.primitive) # TRUE: it is a function, but .. is.primitive(is.primitive) # FALSE: it's not a primitive one, whereas is.primitive(is.function) # TRUE: that one *is*
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Licensed under the GNU General Public License.