On Fri, Jul 18, 2014 at 4:00 PM, Dario Strbenac
<dstr7320 at uni.sydney.edu.au> wrote:
Hello,
capture.output produces a different result if the S4 object was created with a constructor than if the body of the constructor is copied and pasted.
setClass("TransformParams", representation(
transform = "function",
otherParams = "list")
)
setGeneric("TransformParams", function(transform, ...)
{standardGeneric("TransformParams")})
setMethod("TransformParams", character(0), function()
{
new("TransformParams", transform = function(){}, otherParams = list())
})
capture.output(TransformParams()@transform)
[1] "function () " "{"
[3] "}" "<environment: 0x363bd60>"
capture.output(new("TransformParams", transform = function(){}, otherParams = list())@transform)
[1] "function(){}"
Why is the function split into three parts if a constructor is used ?
--------------------------------------
Dario Strbenac
PhD Student
University of Sydney
Camperdown NSW 2050
Australia
Dario, When you use the constructor, the environment of the function is the environment inside the constructor; when you use new() it is R_GlobalEnv The way functions print is that they print their environment when it isn't something special like R_GlobalEnv. Since capture.output captures the printed output, that's what it sees. The function isn't split up; the printed output is. -thomas
Thomas Lumley Professor of Biostatistics University of Auckland