You could use local(), as in
> F <- local({
+ Y <- 3
+ function(x) x * Y
+ })
> F(7)
[1] 21
> Y <- 19
> F(5)
[1] 15
Look into 'environments' for more.
Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com
> -----Original Message-----
> From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On
> Behalf
> Of Schoenfeld, David Alan,Ph.D.,Biostatistics
> Sent: Monday, August 06, 2012 2:08 PM
> To: 'r-help@r-project.org'
> Subject: [R] Force evaluation of a symbol when a function is created
>
>
> I am porting a program in matlab to R,
> The problem is that Matlab has a feature where symbols that aren't arguments
> are
> evaluated immediately.
> That is:
> Y=3
> F=@(x) x*Y
>
> Will yield a function such that F(2)=6.
> If later say. Y=4 then F(2) will still equal 6.
>
> R on the other hand has lazy evaluation.
> F<-function(x){x*Y}
> Will do the following
> Y=3
> F(2)=6
> Y=4
> F(2)=8.
> Does anyone know of away to defeat lazy evaluation in R so that I can easily
> simulate the
> Matlab behavior. I know that I can live without this in ordinary programming
> but it would
> make my port much easier.
>
> Thanks.
>
>
>
>
> The information in this e-mail is intended only for the ...{{dropped:14}}
>
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