checkTnF: Check R Packages or Code for T/F

Description

Checks the specified R package or code file for occurrences of T or F, and gathers the expression containing these. This is useful as in R T and F are just variables which are set to the logicals TRUE and FALSE by default, but are not reserved words and hence can be overwritten by the user. Hence, one should always use TRUE and FALSE for the logicals.

Usage

checkTnF(package, dir, file, lib.loc = NULL)

Arguments

package

a character string naming an installed package. If given, the installed R code and the examples in the documentation files of the package are checked. R code installed as an image file cannot be checked.

dir

a character string specifying the path to a package's root source directory. This must contain the subdirectory R (for R code), and should also contain man (for documentation). Only used if package is not given. If used, the R code files and the examples in the documentation files are checked.

file

the name of a file containing R code to be checked. Used if neither package nor dir are given.

lib.loc

a character vector of directory names of R libraries, or NULL. The default value of NULL corresponds to all libraries currently known. The specified library trees are used to search for package.

Value

An object of class "checkTnF" which is a list containing, for each file where occurrences of T or F were found, a list with the expressions containing these occurrences. The names of the list are the corresponding file names. There is a print method for nicely displaying the information contained in such objects.