Re: [Rd] problem with pipes, textConnection and read.dcf
> peter dalgaard
> on Tue, 10 Aug 2021 22:00:16 +0200 writes:
> It's not a pipe issue:
>> textConnection(gsub(gsub(L, pattern = " ", replacement = ""), pattern =
" ", replacement = ""))
> Error in textConnection(gsub(gsub(L, pattern = " ", replacement = ""), :
> argument 'object' must deparse to a single character string
>> textConnection(gsub(L, pattern = " ", replacement = ""))
> A connection with
> description "gsub(L, pattern = \" \", replacement = \"\")"
> class "textConnection"
> mode"r"
> text"text"
> opened "opened"
> can read"yes"
> can write "no"
> I suppose the culprit is that the deparse(substitute(...)) construct in
the definition of textConnection() can generate multiple lines if the object
expression gets complicated.
>> textConnection
> function (object, open = "r", local = FALSE, name =
deparse(substitute(object)),
> encoding = c("", "bytes", "UTF-8"))
> This also suggests that setting name=something might be a cure.
> -pd
Indeed.
In R 4.0.0, I had introduced the deparse1() short cut to be used
in place of deparse() in such cases:
NEWS has said
• New function deparse1() produces one string, wrapping deparse(),
to be used typically in deparse1(substitute(*)), e.g., to fix
PR#17671.
and the definition is a simple but useful oneliner
deparse1 <- function (expr, collapse = " ", width.cutoff = 500L, ...)
paste(deparse(expr, width.cutoff, ...), collapse = collapse)
So I'm almost sure we should use deparse1() in textConnection
(and will make check and potentially commit that unless ...)
Martin
>> On 10 Aug 2021, at 21:33 , Gabor Grothendieck
wrote:
>>
>> This gives an error bit if the first gsub line is commented out then
there is no
>> error even though it is equivalent code.
>>
>> L <- c("Variable:id", "Length:112630 ")
>>
>> L |>
>> gsub(pattern = " ", replacement = "") |>
>> gsub(pattern = " ", replacement = "") |>
>> textConnection() |>
>> read.dcf()
>> ## Error in textConnection(gsub(gsub(L, pattern = " ", replacement =
""), :
>> ## argument 'object' must deparse to a single character string
>>
>> That is this works:
>>
>> L |>
>> # gsub(pattern = " ", replacement = "") |>
>> gsub(pattern = " ", replacement = "") |>
>> textConnection() |>
>> read.dcf()
>> ## Variable Length
>> ## [1,] "id" "112630"
>>
>> R.version.string
>> ## [1] "R version 4.1.0 RC (2021-05-16 r80303)"
>> win.version()
>> ## [1] "Windows 10 x64 (build 19042)"
>>
>> --
>> Statistics & Software Consulting
>> GKX Group, GKX Associates Inc.
>> tel: 1-877-GKX-GROUP
>> email: ggrothendieck at gmail.com
>>
>> __
>> R-devel@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
> --
> Peter Dalgaard, Professor,
> Center for Statistics, Copenhagen Business School
> Solbjerg Plads 3, 2000 Frederiksberg, Denmark
> Phone: (+45)38153501
> Office: A 4.23
> Email: pd@cbs.dk Priv: pda...@gmail.com
> __
> R-devel@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
__
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Re: [Rd] problem with pipes, textConnection and read.dcf
It's not a pipe issue:
> textConnection(gsub(gsub(L, pattern = " ", replacement = ""), pattern = " ",
> replacement = ""))
Error in textConnection(gsub(gsub(L, pattern = " ", replacement = ""), :
argument 'object' must deparse to a single character string
> textConnection(gsub(L, pattern = " ", replacement = ""))
A connection with
description "gsub(L, pattern = \" \", replacement = \"\")"
class "textConnection"
mode"r"
text"text"
opened "opened"
can read"yes"
can write "no"
I suppose the culprit is that the deparse(substitute(...)) construct in the
definition of textConnection() can generate multiple lines if the object
expression gets complicated.
> textConnection
function (object, open = "r", local = FALSE, name =
deparse(substitute(object)),
encoding = c("", "bytes", "UTF-8"))
This also suggests that setting name=something might be a cure.
-pd
> On 10 Aug 2021, at 21:33 , Gabor Grothendieck wrote:
>
> This gives an error bit if the first gsub line is commented out then there is
> no
> error even though it is equivalent code.
>
> L <- c("Variable:id", "Length:112630 ")
>
> L |>
>gsub(pattern = " ", replacement = "") |>
>gsub(pattern = " ", replacement = "") |>
>textConnection() |>
>read.dcf()
> ## Error in textConnection(gsub(gsub(L, pattern = " ", replacement = ""), :
> ## argument 'object' must deparse to a single character string
>
> That is this works:
>
> L |>
># gsub(pattern = " ", replacement = "") |>
>gsub(pattern = " ", replacement = "") |>
>textConnection() |>
>read.dcf()
> ## Variable Length
> ## [1,] "id" "112630"
>
> R.version.string
> ## [1] "R version 4.1.0 RC (2021-05-16 r80303)"
> win.version()
> ## [1] "Windows 10 x64 (build 19042)"
>
> --
> Statistics & Software Consulting
> GKX Group, GKX Associates Inc.
> tel: 1-877-GKX-GROUP
> email: ggrothendieck at gmail.com
>
> __
> R-devel@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
--
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd@cbs.dk Priv: pda...@gmail.com
__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
[Rd] problem with pipes, textConnection and read.dcf
This gives an error bit if the first gsub line is commented out then there is no
error even though it is equivalent code.
L <- c("Variable:id", "Length:112630 ")
L |>
gsub(pattern = " ", replacement = "") |>
gsub(pattern = " ", replacement = "") |>
textConnection() |>
read.dcf()
## Error in textConnection(gsub(gsub(L, pattern = " ", replacement = ""), :
## argument 'object' must deparse to a single character string
That is this works:
L |>
# gsub(pattern = " ", replacement = "") |>
gsub(pattern = " ", replacement = "") |>
textConnection() |>
read.dcf()
## Variable Length
## [1,] "id" "112630"
R.version.string
## [1] "R version 4.1.0 RC (2021-05-16 r80303)"
win.version()
## [1] "Windows 10 x64 (build 19042)"
--
Statistics & Software Consulting
GKX Group, GKX Associates Inc.
tel: 1-877-GKX-GROUP
email: ggrothendieck at gmail.com
__
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
