Allowing nulls to be passed through tryCatch
I have a simple function that checks whether two supplied arguments are characters, and if not, throws an error
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
check_args_are_chr("one", 2)
> Error in value[[3L]](cond) : Arguments must be supplied as characters
However, arg2 is an optional argument which isn't always passed into the function. NULL is also an acceptable value
I wanted to incorporate it so the expr passed to stopifnot was
is.character(arg2) && is.null(arg2)
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2) && is.null(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
But this still makes the tryCatch throw an exception. How can I modify this so that acceptable classes are character or NULL
r try-catch
edited Nov 26 '18 at 6:29
DTYK
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
add a comment |
I have a simple function that checks whether two supplied arguments are characters, and if not, throws an error
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
check_args_are_chr("one", 2)
> Error in value[[3L]](cond) : Arguments must be supplied as characters
However, arg2 is an optional argument which isn't always passed into the function. NULL is also an acceptable value
I wanted to incorporate it so the expr passed to stopifnot was
is.character(arg2) && is.null(arg2)
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2) && is.null(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
But this still makes the tryCatch throw an exception. How can I modify this so that acceptable classes are character or NULL
r try-catch
edited Nov 26 '18 at 6:29
DTYK
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
1
Simple: you cannot have bothis.characterandis.nullreturnTRUE. Use logical||, not&&.
– Rui Barradas
Nov 25 '18 at 21:30
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35
add a comment |
I have a simple function that checks whether two supplied arguments are characters, and if not, throws an error
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
check_args_are_chr("one", 2)
> Error in value[[3L]](cond) : Arguments must be supplied as characters
However, arg2 is an optional argument which isn't always passed into the function. NULL is also an acceptable value
I wanted to incorporate it so the expr passed to stopifnot was
is.character(arg2) && is.null(arg2)
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2) && is.null(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
But this still makes the tryCatch throw an exception. How can I modify this so that acceptable classes are character or NULL
r try-catch
edited Nov 26 '18 at 6:29
DTYK
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
I have a simple function that checks whether two supplied arguments are characters, and if not, throws an error
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
check_args_are_chr("one", 2)
> Error in value[[3L]](cond) : Arguments must be supplied as characters
However, arg2 is an optional argument which isn't always passed into the function. NULL is also an acceptable value
I wanted to incorporate it so the expr passed to stopifnot was
is.character(arg2) && is.null(arg2)
check_args_are_chr <- function(arg1, arg2){
tryCatch({
stopifnot(is.character(arg1), is.character(arg2) && is.null(arg2))},
error = function(e) stop("Arguments must be supplied as characters"))
}
But this still makes the tryCatch throw an exception. How can I modify this so that acceptable classes are character or NULL
r try-catch
r try-catch
edited Nov 26 '18 at 6:29
DTYK
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
edited Nov 26 '18 at 6:29
DTYK
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
edited Nov 26 '18 at 6:29
DTYK
7041119
edited Nov 26 '18 at 6:29
DTYK
7041119
edited Nov 26 '18 at 6:29
DTYK
7041119
7041119
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
asked Nov 25 '18 at 21:15
Conor NeilsonConor Neilson
452414
452414
1
Simple: you cannot have bothis.characterandis.nullreturnTRUE. Use logical||, not&&.
– Rui Barradas
Nov 25 '18 at 21:30
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35
add a comment |
1
Simple: you cannot have bothis.characterandis.nullreturnTRUE. Use logical||, not&&.
– Rui Barradas
Nov 25 '18 at 21:30
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35
1
1
Simple: you cannot have both
is.character and is.null return TRUE. Use logical ||, not &&.– Rui Barradas
Nov 25 '18 at 21:30
Simple: you cannot have both
is.character and is.null return TRUE. Use logical ||, not &&.– Rui Barradas
Nov 25 '18 at 21:30
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35
add a comment |
2 Answers
2
active
oldest
votes
First your code doesn't work as expected because you are confusing (binary) or || with and &&
Second, using tryCatch this way doesn't really make sense imho. Just do if (...) stop("Arguments must be supplied as characters"). On the downside the if statement is more awkward this way, but less awkward than using tryCatch.
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
Yep, swapping to||worked great, thanks.
– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this contexttryCatchdoesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makestryCatchmore useful, but I just wanted to make sure I got an answer that works with the functions context
– Conor Neilson
Nov 25 '18 at 21:41
add a comment |
Either use missing to check whether arg2 was given:
(missing(arg2) || (is.null(arg2) || is.character(arg2)))
or set a default value arg2 = NULL
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
First your code doesn't work as expected because you are confusing (binary) or || with and &&
Second, using tryCatch this way doesn't really make sense imho. Just do if (...) stop("Arguments must be supplied as characters"). On the downside the if statement is more awkward this way, but less awkward than using tryCatch.
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
Yep, swapping to||worked great, thanks.
– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this contexttryCatchdoesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makestryCatchmore useful, but I just wanted to make sure I got an answer that works with the functions context
– Conor Neilson
Nov 25 '18 at 21:41
add a comment |
First your code doesn't work as expected because you are confusing (binary) or || with and &&
Second, using tryCatch this way doesn't really make sense imho. Just do if (...) stop("Arguments must be supplied as characters"). On the downside the if statement is more awkward this way, but less awkward than using tryCatch.
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
Yep, swapping to||worked great, thanks.
– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this contexttryCatchdoesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makestryCatchmore useful, but I just wanted to make sure I got an answer that works with the functions context
– Conor Neilson
Nov 25 '18 at 21:41
add a comment |
First your code doesn't work as expected because you are confusing (binary) or || with and &&
Second, using tryCatch this way doesn't really make sense imho. Just do if (...) stop("Arguments must be supplied as characters"). On the downside the if statement is more awkward this way, but less awkward than using tryCatch.
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
First your code doesn't work as expected because you are confusing (binary) or || with and &&
Second, using tryCatch this way doesn't really make sense imho. Just do if (...) stop("Arguments must be supplied as characters"). On the downside the if statement is more awkward this way, but less awkward than using tryCatch.
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
answered Nov 25 '18 at 21:37
Stefan FStefan F
7461613
7461613
Yep, swapping to||worked great, thanks.
– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this contexttryCatchdoesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makestryCatchmore useful, but I just wanted to make sure I got an answer that works with the functions context
– Conor Neilson
Nov 25 '18 at 21:41
add a comment |
Yep, swapping to||worked great, thanks.
– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this contexttryCatchdoesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makestryCatchmore useful, but I just wanted to make sure I got an answer that works with the functions context
– Conor Neilson
Nov 25 '18 at 21:41
Yep, swapping to
|| worked great, thanks.– Conor Neilson
Nov 25 '18 at 21:40
Yep, swapping to
|| worked great, thanks.– Conor Neilson
Nov 25 '18 at 21:40
Yes, in this context
tryCatch doesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makes tryCatch more useful, but I just wanted to make sure I got an answer that works with the functions context– Conor Neilson
Nov 25 '18 at 21:41
Yes, in this context
tryCatch doesn't make much sense. It's because I'm trimming down to a minimal example. The full function contains more code that makes tryCatch more useful, but I just wanted to make sure I got an answer that works with the functions context– Conor Neilson
Nov 25 '18 at 21:41
add a comment |
Either use missing to check whether arg2 was given:
(missing(arg2) || (is.null(arg2) || is.character(arg2)))
or set a default value arg2 = NULL
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
add a comment |
Either use missing to check whether arg2 was given:
(missing(arg2) || (is.null(arg2) || is.character(arg2)))
or set a default value arg2 = NULL
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
add a comment |
Either use missing to check whether arg2 was given:
(missing(arg2) || (is.null(arg2) || is.character(arg2)))
or set a default value arg2 = NULL
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
Either use missing to check whether arg2 was given:
(missing(arg2) || (is.null(arg2) || is.character(arg2)))
or set a default value arg2 = NULL
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
answered Nov 25 '18 at 21:34
Kamil BartońKamil Bartoń
1,12469
1,12469
add a comment |
add a comment |
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1
Simple: you cannot have both
is.characterandis.nullreturnTRUE. Use logical||, not&&.– Rui Barradas
Nov 25 '18 at 21:30
Ugh, not sure why I couldn't see that. Cheers
– Conor Neilson
Nov 25 '18 at 21:35