If I try ls with an unquoted version of something in my search list, I
get an error message but the ls completes successfully. For example:
> attach("x.RData")
> ls(file:x.RData)
Error in try(name) : object 'x.RData' not found
[1] "x"
which seems to be because ls first does: nameValue <- try(name) which
raises the error, and then goes on to do some
substitute(deparse(magic)) to get the name and carries on as if I'd
done ls("file:x.RData")
Documentation says (with my enumeration):
The ?name? argument can specify the environment from which object
names are taken in one of several forms:
1. as an integer (the position in the ?search? list);
2. as the character string name of an element in the search list;
3. or as an explicit ?environment?
Either ls(file:x.RData) is none of these in which case there should be
an error and exit, or it's (2), in which case the error is misleading.
I think try(name,silent=TRUE) might be a better option?
Barry
An ls error which is not an error...
2 messages · Barry Rowlingson, Duncan Murdoch
On 09/09/2010 5:57 AM, Barry Rowlingson wrote:
If I try ls with an unquoted version of something in my search list, I get an error message but the ls completes successfully. For example:
> attach("x.RData")
> ls(file:x.RData)
Error in try(name) : object 'x.RData' not found
[1] "x"
which seems to be because ls first does: nameValue <- try(name) which
raises the error, and then goes on to do some
substitute(deparse(magic)) to get the name and carries on as if I'd
done ls("file:x.RData")
Documentation says (with my enumeration):
The ?name? argument can specify the environment from which object
names are taken in one of several forms:
1. as an integer (the position in the ?search? list);
2. as the character string name of an element in the search list;
3. or as an explicit ?environment?
Either ls(file:x.RData) is none of these in which case there should be
an error and exit, or it's (2), in which case the error is misleading.
I think try(name,silent=TRUE) might be a better option?
This is old code, so I don't think converting it to an error is a good idea. I don't like the idea of silently eating the error: it might have been a typo, that just coincidentally looks like the name of something on the search list. So I will try to change the error to an informative warning. Duncan Murdoch