[R] Issue with special assignment operator

[Jeff Newmiller]

Because x refers to the local version, not the global one.

In case you have not read this before, using <<- is a really really bad idea. Your code will become confusing and likely be wrong if you ignore this warning. Return a value from the function and save it in the calling environment when you call the function.
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Sent from my phone. Please excuse my brevity.

On March 16, 2014 9:06:13 PM PDT, AROONALOK PYNE <aroonalok.pyne at gmail.com> wrote:
>Hi
>
>Please explain why the function 'foo()' is not printing x as 8 in the
>following code :
>
>> foo <- function(){
>+ x <- 10
>+ if(x){
>+ x <<- 8
>+ }
>+ print(x)
>+ }
>> foo()
>[1] 10
>> x
>[1] 8
>>