Rのスコープとフレームと環境と

R
parent.env parent.frame
Tokyo.Lang.R #0 (2012/02/19)
@a_bicky

• Takeshi Arabiki
‣

‣ Twitter & : @a_bicky & id:a_bicky

•
R

•
http://d.hatena.ne.jp/a_bicky/

R

Tokyo.R #16 Tsukuba.R #9 R 2011

http://www.slideshare.net/abicky/r-9034336 http://www.slideshare.net/abicky/r-10128090 http://www.slideshare.net/abicky/rtwitter

R

• R
• parent.env parent.frame
•
•

> x <- "x of R_GlobalEnvn"
> f <- function() {
+ x <- "x of function fn"
+ g()
+ # f x
+ h <- function() cat("h:", x)
+ h()
+ }
> # R_GlobalEnv x
> g <- function() cat("g:", x)
> f() # f g, h
g: x of R_GlobalEnv
h: x of function f
> g() # g
g: x of R_GlobalEnv

> x <- "x of R_GlobalEnvn"
> # parent.frame()
> f <- function() {
+ x <- "x of function fn"
+ g()
+ # f f x
+ h <- function() cat("h:", evalq(x, parent.frame()))
+ h()
+ }
> # x
> g <- function() cat("g:", evalq(x, parent.frame()))
> f() # f g, h
g: x of function f
h: x of function f
> g() # g
g: x of R_GlobalEnv

R

(enclosing environment)

> x <- 1; y <- 1 R_GlobalEnv
> f <- function(x) print(x) x = 1
> f(2) y = 1
[1] 2

f

x = 2

parent.env

enclosing environment

parent.frame

caller’s environment

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> h1 <- function() NULL
>

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> f()
f f()

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> h2 <- function() NULL callee g
g()
> f()
caller f

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
callee h1
h1()
> h2 <- function() NULL caller g
> f()
f

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> h2 <- function() NULL g
> f()
f

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
callee h2
h2()
> h2 <- function() NULL caller g
> f()
f

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> f()
f

> f <- function() {
+ g()
+ }
> g <- function() {
+ h1()
+ h2()
+ }
> f()
NULL

parent.env 1
> f <- function() {
+ e <- environment()
+ cat("environment of f: "); print(e)
+ cat("parent environment of f: "); print(parent.env(e))
+ g <- function() { # f g
+ cat("environment of g: "); print(e)
+ cat("parent environment of g: "); print(parent.env(e))
+ }
+ g()
+ }
> f()
environment of f: <environment: 0x105acb7c0>
parent environment of f: <environment: R_GlobalEnv>
environment of g: <environment: 0x105acf228>
parent environment of g: <environment: 0x105acb7c0>

parent.env 1
> f <- function() {
+ }
+ g()
+ } f parent.env R_GlobalEnv g parent.env f
> f()
environment of f: <environment: 0x105acb7c0>
environment of g: <environment: 0x105acf228>
parent environment of g: <environment: 0x105acb7c0>

parent.env 2
> f <- function() {
+ g()
+ }
> g <- function() { # f R_GlobalEnv g
+ }
> f()
environment of f: <environment: 0x105adbad0>
environment of g: <environment: 0x105adf638>
parent environment of g: <environment: R_GlobalEnv>

parent.env 2
> f <- function() {
+ g()
+ }
+ } f parent.env g parent.env R_GlobalEnv
> f()
environment of f: <environment: 0x105adbad0>
environment of g: <environment: 0x105adf638>
parent environment of g: <environment: R_GlobalEnv>

parent.frame 1
> f <- function() {
+ cat("parent environment of f: "); print(parent.frame())
+ cat("parent environment of g: "); print(parent.frame())
+ }
+ g()
+ }
> f()
environment of f: <environment: 0x105ae7670>
environment of g: <environment: 0x105aeb110>
parent environment of g: <environment: 0x105ae7670>

parent.frame 1
> f <- function() {
+ }
+ g()
+ } f parent.frame R_GlobalEnv g parent.frame f
> f()
environment of f: <environment: 0x105ae7670>
environment of g: <environment: 0x105aeb110>
parent environment of g: <environment: 0x105ae7670>

parent.frame 2
> f <- function() {
+ g()
+ }
+ }
> f()
environment of f: <environment: 0x105aef440>
environment of g: <environment: 0x105aee7c0>
parent environment of g: <environment: 0x105aef440>

parent.frame 2
> f <- function() {
+ g()
+ }
+ } f parent.frame R_GlobalEnv g parent.frame f
> f()
environment of f: <environment: 0x105aef440>
environment of g: <environment: 0x105aee7c0>
parent environment of g: <environment: 0x105aef440>

> x <- "x of R_GlobalEnv" R_GlobalEnv
> f <- function() {
+ x <- "x of function f" x = "x of R_GlobalEnv"
+ g <- function() {
+ cat("x in g:", x, "n")
+ }
+ g(); h() f
+ }
x = "x of function f"
> h <- function() {
+ cat("x in h:", x, "n")
+ }
>
g h

> f <- function() {
+ g <- function() {
+ cat("x in g:", x, "n")
+ }
+ g(); h() f
+ }
> h <- function() {
+ cat("x in h:", x, "n")
+ }
> f()
g h

> f <- function() {
+ g <- function() {
+ cat("x in g:", x, "n")
+ }
+ g(); h() f
+ }
> h <- function() {
+ cat("x in h:", x, "n")
+ } g()
> f()
x in g: x of function f g h


> f <- function() {
+ g <- function() {
+ cat("x in g:", x, "n")
+ }
+ g(); h() f
+ }
> h <- function() {
+ cat("x in h:", x, "n")
h()
+ }
> f()
x in g: x of function f g h
x in h: x of R_GlobalEnv

parent.frame parent.env

Rのスコープとフレームと環境と

> search() # R_GlobalEnv base package
[1] ".GlobalEnv" "package:stats" "package:graphics"
[4] "package:grDevices" "package:utils" "package:datasets"
[7] "package:methods" "Autoloads" "package:base"
> attach(iris); search() # iris 2
[1] ".GlobalEnv" "iris" "package:stats"
[4] "package:graphics" "package:grDevices" "package:utils"
[7] "package:datasets" "package:methods" "Autoloads"
[10] "package:base"
> parent.env(globalenv()) # 2 R_GlobalEnv
<environment: 0x100cd62b0>
attr(,"name")
[1] "iris"

> x <- "x of R_GlobalEnv" base package
> l <- list(y = "y of l") .Last.value
> attach(l)
>

l
y = "y of l"

R_GlobalEnv
x = "x of R_GlobalEnv"
l = list(y = "y of l")

> attach(l)
> x
[1] "x of R_GlobalEnv"
>
l
y = "y of l"

R_GlobalEnv

> attach(l)
> x
> y
[1] "y of l" l
> y = "y of l"

R_GlobalEnv

> attach(l)
> x
> y
[1] "y of l" l
> .Last.value y = "y of l"
[1] "y of l"
>
R_GlobalEnv

> attach(l)
> x
> y
[1] "y of l" l
[1] "y of l"
> y <- "y of R_GlobalEnv"
> R_GlobalEnv
y = "y of R_GlobalEnv"

> attach(l)
> x
> y
[1] "y of l" l
[1] "y of l"
> y <- "y of R_GlobalEnv"
> y R_GlobalEnv
[1] "y of R_GlobalEnv" x = "x of R_GlobalEnv"
y = "y of R_GlobalEnv"

> counter <- function(cnt) {
+ function() { # <<-
+ cnt <<- cnt + 1; print(cnt)
+ }
+ }
> c1 <- counter(1); c1 #
function() {
cnt <<- cnt + 1; print(cnt)
}
<environment: 0x1020374a0>
> ls.str(environment(c1)) # cnt
cnt : num 1
> c1(); c1() # cnt
[1] 2
[1] 3

> counter <- function(cnt) { R_GlobalEnv
+ function() {
+ cnt <<- cnt + 1
+ print(cnt) counter(1)
+ }
counter
+ }
> c1 <- counter(1) cnt = 1
>

c1

+ function() {
+ cnt <<- cnt + 1
+ print(cnt)
+ }
counter
+ }
> c1()
c1()
[1] 2
c1

+ function() {
+ cnt <<- cnt + 1
+ print(cnt)
+ }
counter
+ }
> c1()
c1()
[1] 2
> c1() c1
[1] 3

• R
• parent.env
enclosing environment
• parent.frame
caller’s environment
•
•

• R Language Deﬁnition http://cran.r-project.org/doc/manuals/R-lang.pdf
2.1.10 Environment, 3.5 Scope of variables, 4.3.4 Scope
• R Internals http://cran.r-project.org/doc/manuals/R-ints.pdf
1.2 Environments and variable lookup
• Frames, Environments, and Scope in R and S-PLUS
http://cran.r-project.org/doc/contrib/Fox-Companion/appendix-scope.pdf
• ,R , C&R , 2012
SECTION 208, 209
• U. ( ), ( ), R ,
, 2006
4.3

• R http://www.slideshare.net/shuyo/r-4022379

• environment http://user.ecc.u-tokyo.ac.jp/~s105503/p02.html

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