R devel - Jul 2007 - parse(text=...) and the srcfile attribute

Hi,

I'm trying to understand whether the new source file references can
help me with something I want to do. Let's say I have

foo <- parse(text = "
a <- 1; b <- 2**2
a + b
")

I now wish to recover the sources for the parsed expressions. I can
get them one at a time:
> foo[[2]]
b <- 2^2
> as.character(attr(foo, "srcref")[[2]])
[1] "b <- 2**2"

Is there a better way? Perhaps like the print method
> as.character(foo, useSource = TRUE)
could give all the sources at once?

-Deepayan

You can do this:
> foo at srcfile$lines
[1] "\na <- 1; b <- 2**2\na + b\n"
> # or this
> as.character(foo)
[1] "a <- 1"   "b <- 2^2" "a + b"

On 7/12/07, Deepayan Sarkar <deepayan.sarkar at gmail.com>
wrote:
> Hi,
>
> I'm trying to understand whether the new source file references can
> help me with something I want to do. Let's say I have
>
> foo <- parse(text = "
> a <- 1; b <- 2**2
> a + b
> ")
>
> I now wish to recover the sources for the parsed expressions. I can
> get them one at a time:
>
> > foo[[2]]
> b <- 2^2
> > as.character(attr(foo, "srcref")[[2]])
> [1] "b <- 2**2"
>
> Is there a better way? Perhaps like the print method
>
> > as.character(foo, useSource = TRUE)
>
> could give all the sources at once?
>
> -Deepayan
>
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