I have been searching around for some time, but with no luck for this
particular problem.

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On Sat, Feb 1, 2014 at 9:02 AM, Ista Zahn <istazahn@gmail.com> wrote:

> This has been discussed extensively, on this list as well as
> elsewhere. I suggest doing a web search, read up on the issue, and
> post back here only if you have specific questions that are not
> answered already.
>
> Best,
> Ista
>
> On Sat, Feb 1, 2014 at 11:40 AM, Hai Qian <hqian@gopivotal.com> wrote:
> > I know using eval is not optimal and maybe bad, but how to avoid using
> eval
> > in the following example
> >
> > func1 <- function(dat, eval.this) {
> >     eval(parse(text = paste0("with(dat, ", eval.this, ")")))
> > }
> >
> > dat <- data.frame(x = 1:2, y = 2:3)
> >
> > func1(dat, "x*2+y")
> >
> > func1(dat, "sin(x)*cos(y)")
> >
> > Here eval.this is a string that contains whatever the user wants to
> > evaluate. I wonder whether there is a neat way to avoid using eval in
> this
> > case? So far I have not figured out a way to do this.
> >
> >         [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help@r-project.org mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
>

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