[R] eval parent.frame() twice

Rune Schjellerup Philosof
2009-08-07T10:19:23Z

Hi

I want to use a function (update) that in its body uses
eval(call, parent.frame())

I would like to use this function in a function that does not contain
the variables referred to in 'call'. Those variables are instead in the
parent.frame() of my function (named 'second' below)

Like this:
a <- 2

evalu <- function(obj) {
 call <- obj$call
 eval(call, parent.frame())
}
first <- function() {
 a <- 3
 obj <- list(call=expression(a))
 second(obj)
}
second <- function(obj) {
 eval(evalu(obj), parent.frame())
}

first() #returns 2, but I want 3.


How do I change 'second' such that the value of 'a' from
'first' is
returned?

--
Regards
Rune Schjellerup Philosof
Ph.d.-studerende, Statistik, IST, SDU

Telefon:  6550 3607
E-mail:   rphilosof at health.sdu.dk
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