R version 3.1.1 RC (2014-07-04 r66081) -- "Sock it to Me" Copyright (C) 2014 The R Foundation for Statistical Computing Platform: x86_64-unknown-linux-gnu (64-bit) R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details. R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications. Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R. > #### eval / parse / deparse / substitute etc > > ##- From: Peter Dalgaard BSA > ##- Subject: Re: source() / eval() bug ??? (PR#96) > ##- Date: 20 Jan 1999 14:56:24 +0100 > e1 <- parse(text='c(F=(f <- .3), "Tail area" = 2 * if(f < 1) 30 else 90)')[[1]] > e1 c(F = (f <- 0.3), `Tail area` = 2 * if (f < 1) 30 else 90) > str(eval(e1)) Named num [1:2] 0.3 60 - attr(*, "names")= chr [1:2] "F" "Tail area" > mode(e1) [1] "call" > > ( e2 <- quote(c(a=1,b=2)) ) c(a = 1, b = 2) > names(e2)[2] <- "a b c" > e2 c(`a b c` = 1, b = 2) > parse(text=deparse(e2)) expression(c(`a b c` = 1, b = 2)) > > ##- From: Peter Dalgaard BSA > ##- Date: 22 Jan 1999 11:47 > > ( e3 <- quote(c(F=1,"tail area"=pf(1,1,1))) ) c(F = 1, `tail area` = pf(1, 1, 1)) > eval(e3) F tail area 1.0 0.5 > names(e3) [1] "" "F" "tail area" > > names(e3)[2] <- "Variance ratio" > e3 c(`Variance ratio` = 1, `tail area` = pf(1, 1, 1)) > eval(e3) Variance ratio tail area 1.0 0.5 > > > ##- From: Peter Dalgaard BSA > ##- Date: 2 Sep 1999 > > ## The first failed in 0.65.0 : > attach(list(x=1)) > evalq(dim(x) <- 1,as.environment(2)) > dput(get("x", envir=as.environment(2)), control="all") structure(1, .Dim = 1L) > > e <- local({x <- 1;environment()}) > evalq(dim(x) <- 1,e) > dput(get("x",envir=e), control="all") structure(1, .Dim = 1L) > > ### Substitute, Eval, Parse, etc > > ## PR#3 : "..." matching > ## Revised March 7 2001 -pd > A <- function(x, y, ...) { + B <- function(a, b, ...) { match.call() } + B(x+y, ...) + } > (aa <- A(1,2,3)) B(a = x + y, b = 3) > all.equal(as.list(aa), + list(as.name("B"), a = expression(x+y)[[1]], b = 3)) [1] TRUE > (a2 <- A(1,2, named = 3)) #A(1,2, named = 3) B(a = x + y, named = 3) > all.equal(as.list(a2), + list(as.name("B"), a = expression(x+y)[[1]], named = 3)) [1] TRUE > > CC <- function(...) match.call() > DD <- function(...) CC(...) > a3 <- DD(1,2,3) > all.equal(as.list(a3), + list(as.name("CC"), 1, 2, 3)) [1] TRUE > > ## More dots issues: March 19 2001 -pd > ## Didn't work up to and including 1.2.2 > > f <- function(...) { + val <- match.call(expand.dots=FALSE)$... + x <- val[[1]] + eval.parent(substitute(missing(x))) + } > g <- function(...) h(f(...)) > h <- function(...) list(...) > k <- function(...) g(...) > X <- k(a=) > all.equal(X, list(TRUE)) [1] TRUE > > ## Bug PR#24 > f <- function(x,...) substitute(list(x,...)) > deparse(f(a, b)) == "list(a, b)" && + deparse(f(b, a)) == "list(b, a)" && + deparse(f(x, y)) == "list(x, y)" && + deparse(f(y, x)) == "list(y, x)" [1] TRUE > > tt <- function(x) { is.vector(x); deparse(substitute(x)) } > a <- list(b=3); tt(a$b) == "a$b" # tends to break when ... [1] TRUE > > > ## Parser: > 1 < + 2 [1] TRUE > 2 <= + 3 [1] TRUE > 4 >= + 3 [1] TRUE > 3 > + 2 [1] TRUE > 2 == + 2 [1] TRUE > ## bug till ... > 1 != + 3 [1] TRUE > > all(NULL == NULL) [1] TRUE > > ## PR #656 (related) > u <- runif(1); length(find(".Random.seed")) == 1 [1] TRUE > > MyVaR <<- "val";length(find("MyVaR")) == 1 [1] TRUE > rm(MyVaR); length(find("MyVaR")) == 0 [1] TRUE > > > ## Martin Maechler: rare bad bug in sys.function() {or match.arg()} (PR#1409) > callme <- function(a = 1, mm = c("Abc", "Bde")) { + mm <- match.arg(mm); cat("mm = "); str(mm) ; invisible() + } > ## The first two were as desired: > callme() mm = chr "Abc" > callme(mm="B") mm = chr "Bde" > mycaller <- function(x = 1, callme = pi) { callme(x) } > mycaller()## wrongly gave `mm = NULL' now = "Abc" mm = chr "Abc" >