Re: [O] [PATCH] -for review- Tangling with variable transfer of variables

[Rainer M Krug]

Attached please find =the reworked patch. 

1) uses local() and closes connection
2) does not leave a variable cal;led file behind

Cheers,

Rainer

0001-lisp-ob-R.el-Fix-tangling-with-tables.patch
Description: The Patch

Rainer M Krug <address@hidden> writes:

> Charles Berry <address@hidden> writes:
>
>> Aaron Ecay <aaronecay <at> gmail.com> writes:
>>
>>> 
>>> Hi Rainer,
>>> 
>>> I have not tested the patch (I rarely use :var), but here are some
>>> comments from reading the patch.
>>> 
>> [snip]
>>> 
>>> >         (header (if (or (eq (nth 1 value) 'hline) colnames-p)
>>> >                     "TRUE" "FALSE"))
>>> >         (row-names (if rownames-p "1" "NULL")))
>>> >     (if (= max min)
>>> > -       (format "%s <- read.table(\"%s\",
>>> > +       (format "%s <- read.table(textConnection('%s'),
>>> 
>>> This will fail if ‘file’ contains an apostrophe character.  I guess you
>>> need to escape apostrophes in ‘file’.
>>> 
>>
>> There are a bunch of issues with the textConnection - the point Aaron
>> makes, the nasty name (try showConnections() to see), and close()-ing it.
>>
>> I think you need something more like this:
>>
>> ====
>>                  (header (if (or (eq (nth 1 value) 'hline) colnames-p)
>>                               "TRUE" "FALSE"))
>>                   (row-names (if rownames-p "1" "NULL")))
>>               (if (= max min)
>>                   (format "
>>     %s <- 
>>         local({con.object <- 
>>     %S
>>     con <- textConnection(con.object)
>>     res <- read.table(con,
>>                       header=%s,
>>                       row.names=%s,
>>                       sep=\"\\t\",
>>                       as.is=TRUE)
>>     close(con)
>>     res})" 
>>                   name file header row-names)
>>
>> ====
>>
>> Notes: %S handles Aaron's quoting issue.
>>        local() keeps unwanted objects out of user's way.
>>        This worked on a couple of simple tests
>
> I agree completely here - thanks for the %S (didn't know about it - now
> I do) and haven't thought about the local() - I think it is a very good
> idea to use it in the context of the variable transfer.
>
>>
>> If you have `:session :results output' headers your session
>> transcript will have `file' dumped into it, which might be an annoyance.
>
> Not only annoyance - can cause overwriting of the data. Will look into
> this.



>
> Thanks a lot,
>
> Rainer
>
>>
>> HTH,
>>
>> Chuck
>>
>>
>>
>>

-- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation Biology, 
UCT), Dipl. Phys. (Germany)

Centre of Excellence for Invasion Biology
Stellenbosch University
South Africa

Tel :       +33 - (0)9 53 10 27 44
Cell:       +33 - (0)6 85 62 59 98
Fax :       +33 - (0)9 58 10 27 44

Fax (D):    +49 - (0)3 21 21 25 22 44

email:      address@hidden

Skype:      RMkrug

PGP: 0x0F52F982

pgpS5VbUulQol.pgp
Description: PGP signature