R help - Jan 2014 - Curious behaviour of lapply and lists of functions

Let's say I define a simple list of functions, as follows

    lf <- list(
          function(x) x+5,
          function(x) 2*x
       )

Then I can take any individual function from the list and
use it with any value, as it is shown:

    lf[[1]](3)
   [1] 8

    lf[[2]](3)
   [1] 6

this gives me the results I expected.

Then I create a function producer, that just generates a new function
from a given one:

    Producer <- function(f) function(x) 1/f(x)

if I use it with the elements of the list of functions

    Producer(lf[[1]])(3)
   [1] 0.125

    Producer(lf[[2]])(3)
   [1] 0.1666667

again, the result is satisfactory.

However, if I try to produce a list of the new functions, this is
what I get

    linv <- lapply(lf, Producer)

    linv[[1]](3)
   [1] 0.1666667

    linv[[2]](3)
   [1] 0.1666667

Of course this is not what I wanted. 
Could anyone explain me this courious behaviour, and how to get
the two functions in linv?


Thanks,

  -Sergio.

Julio Sergio Santana <juliosergio <at> gmail.com> writes:
> ...
>     Producer <- function(f) function(x) 1/f(x)
> 
Counsulting a previous post, I got to the solution, I just need to rewrite 
the function Producer forcing it to eavaluate its argument, as follows

    Producer <- function(f) {f ;function(x) 1/f(x)}

Then, 

    linv <- lapply(lf, Producer)

    linv[[1]](3)
   [1] 0.125

    linv[[2]](3)
   [1] 0.1666667

Which is the desired result.

Thanks everybody for reading.

  -Sergio.