assert_is_bzfile_connection
From assertive.files v0.0-2
by Richard Cotton
Is the input a connection?
Various checks to see if the input is a (particular type of/open/incomplete) connection.
Usage
assert_is_bzfile_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_fifo_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_file_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_gzfile_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_incomplete_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_open_connection(x, rw = "", severity = getOption("assertive.severity", "stop"))
assert_is_pipe_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_readable_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_socket_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_stderr(x, severity = getOption("assertive.severity", "stop"))
assert_is_stdin(x, severity = getOption("assertive.severity", "stop"))
assert_is_stdout(x, severity = getOption("assertive.severity", "stop"))
assert_is_terminal_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_text_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_unz_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_url_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_writable_connection(x, severity = getOption("assertive.severity", "stop"))
assert_is_xzfile_connection(x, severity = getOption("assertive.severity", "stop"))
is_bzfile_connection(x, .xname = get_name_in_parent(x))
is_connection(x, .xname = get_name_in_parent(x))
is_fifo_connection(x, .xname = get_name_in_parent(x))
is_file_connection(x, .xname = get_name_in_parent(x))
is_gzfile_connection(x, .xname = get_name_in_parent(x))
is_incomplete_connection(x, .xname = get_name_in_parent(x))
is_open_connection(x, rw = "", .xname = get_name_in_parent(x))
is_pipe_connection(x, .xname = get_name_in_parent(x))
is_readable_connection(x, .xname = get_name_in_parent(x))
is_socket_connection(x, .xname = get_name_in_parent(x))
is_stderr(x, .xname = get_name_in_parent(x))
is_stdin(x, .xname = get_name_in_parent(x))
is_stdout(x, .xname = get_name_in_parent(x))
is_terminal_connection(x, .xname = get_name_in_parent(x))
is_text_connection(x, .xname = get_name_in_parent(x))
is_unz_connection(x, .xname = get_name_in_parent(x))
is_url_connection(x, .xname = get_name_in_parent(x))
is_writable_connection(x, .xname = get_name_in_parent(x))
is_xzfile_connection(x, .xname = get_name_in_parent(x))
Arguments
- x
- Input to check.
- severity
- How severe should the consequences of the assertion be?
Either
"stop"
,"warning"
,"message"
, or"none"
. - rw
- Read-write status of connection. Passed to
isOpen
. - .xname
- Not intended to be used directly.
Value
is_connection
checks for objects of class "connection".
is_open_connection
and is_incomplete_connection
wrap
isOpen
and isIncomplete
respectively, providing more
information on failure.
is_readable_connection
and is_writable_connection
tell you
whether the connection is readable from or writable to.
is_bzfile_connection
, is_fifo_connection
,
is_file_connection
, is_pipe_connection
,
is_socket_connection
, is_stderr
, is_stdin
,
is_stdout
, is_text_connection
, is_unz_connection
,
is_url_connection
and is_xzfile_connection
give more
specific tests on the type of connection.
The assert_*
functions return nothing but throw an error if the
corresponding is_*
function returns FALSE
.
Note
is_incomplete_connection
will return false for closed
connections, regardless of whether or not the connection ends with a newline
character.
(isIncomplete
throws an error for closed connections.)
See Also
Examples
library(assertive.files)
assert_is_terminal_connection(stdin())
assert_is_readable_connection(stdin())
assert_is_open_connection(stdin())
assert_is_stdin(stdin())
# Next line is usually true but, e.g., devtools::run_examples overrides it
assertive.base::dont_stop(assert_is_terminal_connection(stdout()))
assert_is_writable_connection(stdout())
assert_is_open_connection(stdout())
assert_is_stdout(stdout())
assert_is_terminal_connection(stderr())
assert_is_writable_connection(stderr())
assert_is_open_connection(stderr())
assert_is_stderr(stderr())
tcon <- textConnection("txt", "w", local = TRUE)
assert_is_text_connection(tcon)
assert_is_open_connection(tcon)
cat("this has no final newline character", file = tcon)
assert_is_incomplete_connection(tcon)
close(tcon)
# These examples should fail.
assertive.base::dont_stop({
assert_is_connection("not a connection")
assert_is_readable_connection(stdout())
assert_is_writable_connection(stdin())
})
## Not run:
# fcon <- file()
# close(fcon)
# assert_is_open_connection(fcon)
# ## End(Not run)
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