Date: 2017-05-06

# Performance benchmarks

#### 2017-05-06

These performance tests are adapted from the R6 performance documentation. I was curious how the implementations in this package would compare to R6 since one of the main design goals of R6 was to solve some performance issues with the reference classes from the methods package.

## Definitions

    library("R6")
    library("aoos")
    library("rbenchmark")

    R6 <- R6Class("R6",
                  public = list(
                    x = NULL,
                    initialize = function(x = 1) self$x <- x,
                    getx = function() self$x,
                    inc = function(n = 1) self$x <- x + n
                  )
    )

    RC <- setRefClass("RC",
                      fields = list(x = "numeric"),
                      methods = list(
                        initialize = function(x = 1) .self$x <- x,
                        getx = function() x,
                        inc = function(n = 1) x <<- x + n
                      )
    )

    RList <- function(x = 1) {
      self <- environment()
      getx <- function() self$x
      inc <- function(n = 1) self$x <- self$x + n
      out <- list(x = x, getx = getx, inc = inc)
      class(out) <- "RList"
      out
    }

    RL <- function(x = 1) {
      getx <- function() .self$x
      inc <- function(n = 1) .self$x <- .self$x + n
      retList("RL", c("x", "getx", "inc"))
    }

    DC <- defineClass("DC", {
      getx <- function() .self$x
      inc <- function(n = 1) .self$x <- .self$x + n
      init <- function(x = 1) .self$x <- x
    })

    # And some more definitions for inheritance
    R6Child <- R6Class("R6Child", inherit = R6)
    RCChild <- setRefClass("RCChild", contains = "RC")
    RLChild <- function(...) {
      retList("RLChild", super = RL(...))
    }
    DCChild <- defineClass("DCChild", contains = "DC", {})

## Results

    benchmark(
      DC(),
      RC$new(),
      R6$new(),
      RL(),
      RList()
    )

    ##       test replications elapsed relative user.self sys.self user.child
    ## 1     DC()          100   0.178      178     0.180        0          0
    ## 3 R6$new()          100   0.007        7     0.004        0          0
    ## 2 RC$new()          100   0.031       31     0.032        0          0
    ## 4     RL()          100   0.003        3     0.004        0          0
    ## 5  RList()          100   0.001        1     0.000        0          0
    ##   sys.child
    ## 1         0
    ## 3         0
    ## 2         0
    ## 4         0
    ## 5         0

    benchmark(
      DCChild(),
      RCChild$new(),
      R6Child$new(),
      RLChild()
    )

    ##            test replications elapsed relative user.self sys.self
    ## 1     DCChild()          100   0.378   34.364     0.380        0
    ## 3 R6Child$new()          100   0.024    2.182     0.024        0
    ## 2 RCChild$new()          100   0.032    2.909     0.032        0
    ## 4     RLChild()          100   0.011    1.000     0.008        0
    ##   user.child sys.child
    ## 1          0         0
    ## 3          0         0
    ## 2          0         0
    ## 4          0         0