Add gg()

DESCRIPTION

@@ -1,14 +1,14 @@
 Package: chart
 Type: Package
-Version: 1.3.1
+Version: 1.4.0
 Title: General Charting (Plotting) Function
 Description: Chart generalizes plot generation in R, being with base R plot
   function, lattice or ggplot2. A formula interface is available for both.
 Authors@R: c(person("Philippe", "Grosjean", role = c("aut", "cre"),
   email = "phgrosjean@sciviews.org",
   comment = c(ORCID = "0000-0002-2694-9471")))
 Maintainer: Philippe Grosjean <phgrosjean@sciviews.org>
-Depends: R (>= 3.3.0), lattice, ggplot2 (>= 3.0)
+Depends: R (>= 4.0.0), lattice, ggplot2 (>= 3.0)
 Imports: stats, utils, rlang, cowplot, grDevices, graphics, scales, latticeExtra, viridis, pryr, data.io, ggplotify, ggpubr
 Suggests: MASS, covr, knitr, testthat, rmarkdown, spelling
 Remotes: SciViews/data.io

NAMESPACE

@@ -1,12 +1,15 @@
 # Generated by roxygen2: do not edit by hand
 
+S3method("$",subsettable_gg)
 S3method("$",subsettable_type)
+S3method(.DollarNames,subsettable_gg)
 S3method(chart,"function")
 S3method(chart,default)
 export(chart)
 export(chart_theme)
 export(combine_charts)
 export(f_aes)
+export(gg)
 export(ggarrange)
 export(theme_sciviews)
 export(theme_sciviews_graphics)
@@ -40,5 +43,7 @@ importFrom(scales,gradient_n_pal)
 importFrom(scales,hue_pal)
 importFrom(stats,as.formula)
 importFrom(stats,asOneSidedFormula)
+importFrom(utils,.DollarNames)
+importFrom(utils,apropos)
 importFrom(utils,modifyList)
 importFrom(viridis,viridis_pal)

NEWS.md

@@ -1,8 +1,12 @@
+# chart 1.4.0
+
+-   The `gg()` subsettable function allows to use the pipe instead of the `+` in ggplot2, like `ggplot() |> gg$geom_point()`. Also, a completion list is available when typing `gg$<tab>`.
+
 # chart 1.3.1
 
 -   Code in `chart.default()` choked `R CMD Check` (variable `y` not defined in scope) is commented out. Expect a slightly different behavior with automatic `geom_point()` with only one variable.
 
--   GitHub repository cleaned up (spelling + GitHub ations added).
+-   GitHub repository cleaned up (spelling + GitHub actions added).
 
 ## chart 1.3.0
 

R/chart-package.R

@@ -22,7 +22,7 @@
 #' @importFrom cowplot theme_cowplot
 #' @importFrom rlang abort warn f_env f_lhs f_rhs is_true is_quosure
 #' @importFrom stats as.formula asOneSidedFormula
-#' @importFrom utils modifyList
+#' @importFrom utils .DollarNames apropos modifyList
 #' @importFrom pryr modify_lang
 #' @importFrom data.io label
 #' @importFrom ggplotify as.ggplot

R/gg.R

@@ -0,0 +1,133 @@
+#' Make a ggplot function pipeable
+#'
+#' @description The function [gg()] should be used like this: `gg$geom_point()`.
+#' It transforms on the fly an original {ggplot2} function supposed to be used
+#' with the `+` operator (like `p + geom_point()`) into a pipeable version
+#' (like `p %>% gg$geom_point()`).
+#'
+#' @param ggplot An object of class "ggplot" (or "theme").
+#' @param ... Further arguments passed to the the ggplot function (see Details).
+#' @param x The `gg()`function.
+#' @param name The name of the ggplot function to make pipeable.
+#' @param pattern A regular expression to list matching names.
+#'
+#' @return The `gg()` function just returns an error message. When subsetted
+#' with the name of a {ggplot2} function (e.g., `gg$geom_point()`), it
+#' returns a modified version of that function in such a way that it can be
+#' used with a pipe operator.
+#'
+#' @details The function returned by `gg$fun` is a modified version of the
+#' function `fun` where a first argument `ggplot =` is added, and the
+#' instruction `ggplot + ...` is added in its body. A message
+#' is also added in the body to explicitly warn about these changes. All the
+#' other arguments of `fun` remain valid and should keep their original meaning.
+#'
+#' The changes are done on the fly, and the original function `fun` is **not**
+#' altered anywhere else (and in particular, no alteration is done in a package
+#' or a namespace). When using this construct, make sure that: (1) you
+#' understand what is done, (2) you are aware that you use an altered version of
+#' the original function, (3) a bug or strange behavior may occur due to the
+#' patch and the original author of the function is not responsible in this case
+#' (the problem must be reported to the author of [gg()] and the maintainer of
+#' the present package instead), and (4) the patched function exhibits an
+#' additional argument and behaves differently to what is described in the help
+#' page of the original, non-patched, function!
+#'
+#' @export
+#'
+#' @examples
+#' library(ggplot2)
+#' data(iris)
+#' ggplot(aes(x = Petal.Length, y = Sepal.Length, col = Species) , data = iris) |>
+#'   gg$geom_point() |>
+#'   gg$labs(x = "Sepal length (mm)", y = "Petal length (mm)")
+#' # Also try completion with gg$<tab>
+gg <- structure(function(ggplot, ...) {
+  stop("You must indicate gg$<something>(), like gg$geom_point() or gg$labs()")
+}, class = c("subsettable_gg", "function"))
+
+.make_pipeable_gg <- function(fun) {
+  if (is.function(fun)) {
+    f <- fun
+  } else {
+    fun_name <- as.character(fun)
+    f <- get0(fun_name, envir = parent.frame(2), mode = "function",
+      inherits = TRUE)
+    if (is.null(f))
+      stop("Cannot found function '", fun_name, "'")
+  }
+  # Change arguments to prepend ggplot =
+  formals(f) <- c(pairlist(ggplot = NULL), formals(f))
+  # Change body: prepend ggplot + {...}
+  patched_body <- body(function(ggplot, ...) {
+    "Warning: this is a patched version of a ggplot function to make it pipeable. Please, read ?gg first!"
+    ggplot + 1
+  })
+  patched_body[[3]][[3]] <- body(f)
+  body(f) <- patched_body
+  f
+}
+
+#' @export
+#' @rdname gg
+#' @method $ subsettable_gg
+`$.subsettable_gg` <- function(x, name) {
+  if (name == "title")
+    name <- "ggtitle"
+  .make_pipeable_gg(name)
+}
+
+#' @export
+#' @rdname gg
+#' @method .DollarNames subsettable_gg
+.DollarNames.subsettable_gg <- function(x, pattern = "") {
+  l <- list("annotate", "expand_limits", "guides", "labs", "lims", "theme",
+    "title", # Instead of ggtitle (special case!)
+    "xlab", "xlim", "ylab", "ylim")
+  l <- grep(pattern = pattern, l, value = TRUE)
+  l <- c(l, apropos(paste0("^geom_", pattern)))
+  l <- c(l, apropos(paste0("^annotation_", pattern)))
+  l <- c(l, apropos(paste0("^coord_", pattern)))
+  l <- c(l, apropos(paste0("^facet_", pattern)))
+  l <- c(l, apropos(paste0("^scale_", pattern)))
+  l <- c(l, apropos(paste0("^stat_", pattern)))
+  l <- c(l, apropos(paste0("^theme_", pattern)))
+  sort(l)
+}
+
+# TODO: allow custom extensions to this list
+# (trials that do not work for now)
+# gg_help_handler <- function(type = c("completion", "parameter", "url"),
+#   topic, source, ...) {
+#   type <- match.arg(type)
+#   if (type == "completion") {
+#     # Just a trial
+#     list(title = "title", signature = "function(x, y)", returns = "1",
+#       description = "desc", details = "details", sections = "sections")
+#   } else if (type == "parameter") {
+#     list(args = c("x", "y"), arg_descriptions = c("x param", "y param"))
+#   } else if (type == "url") {
+#     "https://wp.sciviews.org"
+#   }
+# }
+#
+# .DollarNames.subsettable_gg <- function(x, pattern = "") {
+#   l <- list("annotate", "expand_limits", "guides", "labs", "lims", "theme",
+#     "title", # Instead of ggtitle (special case!)
+#     "xlab", "xlim", "ylab", "ylim")
+#   l <- grep(pattern = pattern, l, value = TRUE)
+#   l <- c(l, apropos(paste0("^geom_", pattern)))
+#   l <- c(l, apropos(paste0("^annotation_", pattern)))
+#   l <- c(l, apropos(paste0("^coord_", pattern)))
+#   l <- c(l, apropos(paste0("^facet_", pattern)))
+#   l <- c(l, apropos(paste0("^scale_", pattern)))
+#   l <- c(l, apropos(paste0("^stat_", pattern)))
+#   l <- c(l, apropos(paste0("^theme_", pattern)))
+#   # This works and my object is recognized as a function, but with only ... arg
+#   #l <- paste0(sort(l), "(")
+#   # This does not work!
+#   #attr(l, "types") <- rep(6, length.out = length(l))
+#   # This does not work!
+#   #attr(l, "helpHandler") <- gg_help_handler
+#   l
+# }

README.md

@@ -6,7 +6,7 @@
 
 <!-- badges: end -->
 
-{chart} propose a formula interface to {ggplot2}, and it also homogenize plot outputs from base R plots, {lattice} and {ggplot}. If labels and/or units attributes are defined for variables in the data, they are used automatically to construct the label (with units) of the axes.
+{chart} proposes a formula interface to {ggplot2}, and it also homogenize plot outputs from base R plots, {lattice} and {ggplot}. If labels and/or units attributes are defined for variables in the data, they are used automatically to construct the label (with units) of the axes.
 
 ## Installation
 

TODO.md

@@ -2,6 +2,8 @@
 
 -   `autoplot()` and `plot()` methods (+ `hist()`, etc.)
 
+-   Implement `.DollarNames()` to get a list of `chart()` types available, with a mechanism to add more types from additional packages.
+
 -   Refine themes and look at themes for {lattice} and base.
 
 -   Use labels for base and {lattice} plots.

inst/WORDLIST

@@ -4,5 +4,7 @@ devtools
 ggplot
 GitHub
 OSX
+pipeable
+subsettable
 thetics
 viridis