r - Passing parameters to with() via function -

there way pass parameter function with()? like:

dados <- data.frame(x=1:10, v1=rnorm(10), v2=rnorm(10))  with(dados, v1+v2) # works  func <- function(data, funcao) {  with(data, funcao) }  func(dados, v1+v2) # fails func(dados, 'v1+v2') # fails 

i've tried eval(), fails :/

ok, think got it. need call eval inside func , pass expression:

dados <- data.frame(x=1:10, v1=rnorm(10), v2=rnorm(10))  func <- function(data, funcao) {      with(data, eval(funcao)) }  func(dados, expression(v1+v2))  [1] -0.9950362  1.0934899 -0.9791810 -1.2420633 -1.0930204  0.8941630 -2.3307571 -1.5012386  3.2731584  0.2585419 

to use string:

x = "v1 + v2" func(dados, parse(text=x))  [1] -0.9950362  1.0934899 -0.9791810 -1.2420633 -1.0930204  0.8941630 -2.3307571 -1.5012386  3.2731584  0.2585419