similar to: Getting ... as an unevaluated list

> lm2 <- function(...) lm(...) > lm2(mpg ~ wt, data=mtcars) Call: lm(formula = ..1, data = ..2) Coefficients: (Intercept) wt 37.285 -5.344 > lm2(mpg ~ wt, weights=cyl, data=mtcars) Error in eval(expr, envir, enclos) : ..2 used in an incorrect context, no ... to look in Can anyone explain why this is happening? (Obviously this is a manufactured example, but it

I would like to take this: .img(plot(1:10), filename="a") and produce plot(1:10) ie. whenever .img is used, I want to take the first argument and throw away everything else. (I am trying to produce a Sweave like environment in which I can apply certain functions, but not have them displayed in the output) I think I should be able to do it using substitute, but I don't know how

Since you're already using bang-bang ;) library(rlang) dots1 <- function(...) as.list(substitute(list(...)))[-1L] dots2 <- function(...) as.list(substitute(...())) dots3 <- function(...) match.call(expand.dots = FALSE)[["..."]] dots4 <- function(...) exprs(...) bench::mark( dots1(1+2, "a", rnorm(3), stop("bang!")), dots2(1+2, "a",

Hi all, I think there's a small buglet in quote: str(quote()) # Error in quote() : 0 arguments passed to 'quote' which requires 1 str(quote(expr = )) # symbol I bring this up because this seems like the most natural way of capturing the "missing" symbol with pure R code, compared to substitute() or bquote() or formals(plot)$x Hadley -- Chief Scientist, RStudio

Can any one provide more details on this error that I'm getting from R CMD check: * checking whether the name space can be loaded with stated dependencies ... WARNING Error in eval(expr, envir, enclos) : could not find function "proto" Error: unable to load R code in package 'ggplot2' Execution halted A namespace must be able to be loaded with just the base namespace

Hi all, It's possible to capture the expression associated with a promise (using substitute). Is there any way to capture the environment associated with a promise? Similarly, is there any way to tell if something is a promise without accidentally evaluating it? Thanks! Hadley -- RStudio / Rice University http://had.co.nz/

On Mon, Jan 26, 2015 at 12:24 PM, Hadley Wickham <h.wickham at gmail.com> wrote: > If it was any other environment than the global, you could use substitute: > > e <- new.env() > delayedAssign("foo", stop("Hey!"), assign.env = e) > substitute(foo, e) > > delayedAssign("foo", stop("Hey!")) > substitute(foo) Hmm... interesting

On Thu, May 3, 2018 at 9:50 AM, Duncan Murdoch <murdoch.duncan at gmail.com> wrote: > On 03/05/2018 11:18 AM, Duncan Murdoch wrote: >> >> On 03/05/2018 11:01 AM, William Dunlap via R-devel wrote: >>> >>> In R-3.5.0 you can use ...length(): >>> > f <- function(..., n) ...length() >>> > f(stop("one"),

Hi, I am getting an error message when I am trying to run the debugger() on the last.dump. The debugger() stops after I make a selection. Could someone please suggest what it might mean? The R log is included below. This is R-1.8.1 on RH 7.3. Thanks, Vadim > load("last.dump.rda") > debugger(last.dump) Message: Error in split(x, f) : Group length is 0 but data length > 0

Hi R-users, I would like to create an expression without evaluating it. Then paste that expression to an object. Example: Result <- paste('Result', 1, sep="") paste(Result, substitute(apply(exp.des[1:10,], 1, one.row, parms=parameters)), sep="<-") However this pastes EACH element of the unevaluated expression. Instead I just would like the expression

Dear developeRs, I maintain a package 'pls', which has a main fit function mvr(), and functions plsr() and pcr() which are meant to take the same arguments as mvr() and do exactly the same, but have different default values for the 'method' argument. The three functions are all exported from the name space. In the 'pre namespace' era, I took inspiration from lm() and

Hi, It would be great if one of the experts could comment on the difference between Hadley's dotlength and ...length? The fact that someone bothered to implement a new primitive for that when there seems to be a very simple and straightforward R-only solution suggests that there might be some gotchas/pitfalls with the R-only solution. Thanks, H. On 05/03/2018 08:34 AM, Hadley Wickham

On Jul 15, 2015, at 12:51 PM, William Dunlap wrote: > I think rapply() was changed to act like lapply() in this respect. > When I looked at the source of the difference, it was that typeof() returned 'language' in 3.2.1, while it returned 'list' in the earlier version of R. The first check in rapply's code in both version was: if (typeof(object) != "list")

Interestingly, as.list(substitute(...())) also works. On Sun, Aug 12, 2018 at 1:16 PM, Duncan Murdoch <murdoch.duncan at gmail.com> wrote: > On 12/08/2018 4:00 PM, Henrik Bengtsson wrote: >> >> Hi. For any number of *known* arguments, we can do: >> >> one <- function(a) list(a = substitute(a)) >> two <- function(a, b) list(a = substitute(a), b =

Dear R Users, I have searched through the archives but I am still struggling to find a way to process the below dataset. I have a dataset that has stratum and plot identifier. Within each plot there is variable (Top) stating the number of measurments that should be used to to calculate the mean to the largest "top" elements within one of the vectors (X). I would like to process

David, If you are referring to the solution that would be: rapply(list(test), eval, envir = fenv) I thought I explained in the question that the above code does not work. It does not throw an error, but the behavior is no different (at least in the output or result). Using the above code still results in the x object not being stored in fenv on 3.1.2. Dayne On Wed, Jul 15, 2015 at 4:40 PM,

Hi all, It seems that there is a use case for obtaining the environment for the "top" promise. By "top", I mean following the promise chain up the call stack until hitting a non-promise. S4 data containers often mimic the API of base R data structures. This means writing S4 methods for functions that quote their arguments, like with() and subset(). The methods package

Your example x = 5 exp = parse(text="f(uq(x)) + y +z") # expression: f(uq(x)) +y + z do_unquote(expr) # -> the language object f(5) + y + z could be done with the following wrapper for bquote my_do_unquote <- function(language, envir = parent.frame()) { if (is.expression(language)) { # bquote does not go into expressions, only calls

Hi all, Does there already exist a version of substitute that evaluates it's first argument? (i.e. it accepts an already quoted expression). This seems like something that's pretty handy, but I haven't found any existing function to do it: substitute_e <- function(expr, env) { eval(substitute(substitute(expr, env), list(expr = expr))) } f <- quote(x + y + z) substitute(f,

This is an expanded version of the question I tried to ask last night - I thought I had it this morning, but it's still not working and I just do not understand what is going wrong. What I am trying to do is write a wrapper for lattice xyplot() that passes a whole bunch of its secondary arguments, so that I can produce similarly formatted graphs for several different data sets. This is what