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R : Copyright 1999, The R Development Core Team
Version 0.65.0 Patched (unreleased) (September 03, 1999)

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> ####  eval / parse / deparse  etc
> 
> ##- From: Peter Dalgaard BSA <p.dalgaard@biostat.ku.dk>
> ##- 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 <p.dalgaard@biostat.ku.dk>
> ##- To: r-core
> ##- Date: 22 Jan 1999 11:47
> ##-   ...
> ##- This is what didn't work before:
> 
> ( 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 <p.dalgaard@biostat.ku.dk>
> ##- To: r-core
> ##- Date: 2 Sep 1999
> 
> ## The first failed in 0.65.0 :
> attach(list(x=1))
> evalq(dim(x) <- 1,pos.to.env(2))
> dput(get("x", env=pos.to.env(2)))
structure(1, .Dim = 1)
> 
> e <- local({x <- 1;environment()})
> evalq(dim(x) <- 1,e)
> dput(get("x",env=e))
structure(1, .Dim = 1)
> 
>