Improved `is.language` function in R -

In R, there is an action that will return TRUE if its argument type < / Code> and FALSE otherwise?

is.language function does not satisfy it because it goes back to for the type of argument symbol or < Also, in the form of the code> expression , I could easily check that the type of argument is language in some way typeof (x) == 'language' Or writes its own work, but it seems strange that R does not already have its function for this purpose because R Not a specific type of those types in most types-type of function.

The only object of type language is not a name < / Code> / symbol or expression is a call for which you can use is.call .