A set of predicates and assertions for checking the files of variables, such as length, names and attributes. Most of the documentation is on the assertive page. End-users will usually want to use assertive directly.
To install the stable version, type:
install.packages("assertive.files")To install the development version, you first need the devtools package.
install.packages("devtools")Then you can install the assertive.files package using
library(devtools)
install_bitbucket("richierocks/assertive.files")Functions for files:
is_dir checks if a path corresponds to a directory.
is_empty_file checks if a path corresponds to an empty file.
is_existing_file checks if a path corresponds to an existing file.
is_readable_file, is_writable_file, and is_executable_file check a file's permissions. (Though they are based upon base::file.access, which sometimes gives unexpected results under Windows.)
is_library checks if a path corresponds to a library that R knows about.
Functions for connections:
is_connection checks if a variable is a connection.
is_bzfile_connection, is_fifo_connection, is_file_connection, is_gzfile_connection, is_pipe_connection, is_socket_connection, is_terminal_connection, is_text_connection, is_unz_connection, and is_url_connection check for these specific connection types.
is_stderr, is_stdin, and is_stdout check for these standard connections.
is_incomplete_connection, is_open_connection, is_readable_connection, and is_writable_connection check for these properties of connections.
Predicates that return a vector have two corresponding assertions. For example, is_dir has assert_all_are_dirs and assert_any_are_dirs.
Predicates returning a single logical value have one corresponding assertion. For example, is_stdin has assert_is_stdin.