Merge commit '581793305286b4a92b10013afead9804174cfeeb'

NAMESPACE

@@ -60,6 +60,7 @@ export(imap_dfr)
 export(imap_int)
 export(imap_lgl)
 export(imap_raw)
+export(imap_vec)
 export(imodify)
 export(insistently)
 export(invoke)

NEWS.md

@@ -1,24 +1,28 @@
 # purrr (development version)
 
 * Added a new keep_empty argument to `list_c()`, `list_cbind()`, and `list_rbind()` which will keep empty elements as `NA` in the returned data frame (@SokolovAnatoliy, #1096).
+* `list_transpose()` now works with data.frames (@KimLopezGuell, #1109).
+* Added `imap_vec()` (#1084)
+* `list_transpose()` inspects all elements to determine the correct
+  template if it's not provided by the user  (#1128, @krlmlr).
 
 # purrr 1.0.2
 
 * Fixed valgrind issue.
 
-* Deprecation infrastructure in `map_chr()` now has much less overhead 
+* Deprecation infrastructure in `map_chr()` now has much less overhead
   leading to improved performance (#1089).
 
 * purrr now requires R 3.5.0.
 
 # purrr 1.0.1
 
 * As of purrr 1.0.0, the `map()` family of functions wraps all errors generated
-  by `.f` inside an wrapper error that tracks the iteration index. As of purrr 
-  1.0.1, this error now has a custom class (`purrr_error_indexed`), 
+  by `.f` inside an wrapper error that tracks the iteration index. As of purrr
+  1.0.1, this error now has a custom class (`purrr_error_indexed`),
   `location` and `name` fields, and is documented in `?purrr_error_indexed`
   (#1027).
-  
+
 * `map()` errors with named inputs also report the name of the element that
   errored.
 
@@ -41,19 +45,19 @@
   See #768 for more information.
 
 * `update_list()` (#858) and `rerun()` (#877), and the use of tidyselect
-  with `map_at()` and friends (#874) have been deprecated. These functions 
-  use some form of non-standard evaluation which we now believe is a poor 
+  with `map_at()` and friends (#874) have been deprecated. These functions
+  use some form of non-standard evaluation which we now believe is a poor
   fit for purrr.
 
 * The `lift_*` family of functions has been deprecated. We no longer believe
-  these to be a good fit for purrr because they rely on a style of function 
+  these to be a good fit for purrr because they rely on a style of function
   manipulation that is very uncommon in R code (#871).
 
-* `prepend()`, `rdunif()`, `rbernoulli()`, `when()`, and `list_along()` have 
+* `prepend()`, `rdunif()`, `rbernoulli()`, `when()`, and `list_along()` have
   all been deprecated (#925). It's now clear that they don't align with the
   core purpose of purrr.
 
-* `splice()` is deprecated because we no longer believe that automatic 
+* `splice()` is deprecated because we no longer believe that automatic
   splicing makes for good UI. Instead use `list2()` + `!!!` or
   `list_flatten()` (#869).
 
@@ -62,33 +66,33 @@
 * Use of map functions with expressions, calls, and pairlists has been
   deprecated (#961).
 
-* All map `_raw()` variants have been deprecated because they are of limited 
+* All map `_raw()` variants have been deprecated because they are of limited
   use and you can now use `map_vec()` instead (#903).
 
 * In `map_chr()`, automatic conversion from logical, integer, and double to
-  character is now deprecated. Use an explicit `as.character()` if needed 
+  character is now deprecated. Use an explicit `as.character()` if needed
   (#904).
 
-* Errors from `.f` are now wrapped in an additional class that gives 
+* Errors from `.f` are now wrapped in an additional class that gives
   information about where the error occurred (#945).
 
 ### Deprecation next steps
 
-* `as_function()` and the `...f` argument to `partial()` are no longer 
+* `as_function()` and the `...f` argument to `partial()` are no longer
   supported. They have been defunct for quite some time.
 
 * Soft deprecated functions: `%@%`, `reduce_right()`, `reduce2_right()`,
-  `accumulate_right()` are now fully deprecated. Similarly, the 
+  `accumulate_right()` are now fully deprecated. Similarly, the
   `.lazy`, `.env`, and `.first` arguments to `partial()`,
-  and the `.right` argument to `detect()` and `detect_index()` 
+  and the `.right` argument to `detect()` and `detect_index()`
   are fully deprecated. Removing elements with `NULL` in `list_modify()` and
   `list_merge()` is now fully deprecated.
 
 * `is_numeric()` and `is_scalar_numeric()` have been removed. They have
   been deprecated since purrr 0.2.3 (Sep 2017).
 
-* `invoke_*()` is now deprecated. It was superseded in 0.3.0 (Jan 2019) and 
-  3.5 years later, we have decided to deprecate it as part of the API 
+* `invoke_*()` is now deprecated. It was superseded in 0.3.0 (Jan 2019) and
+  3.5 years later, we have decided to deprecate it as part of the API
   refinement in the 1.0.0 release.
 
 * `map_call()` has been removed. It was made defunct in 0.3.0 (Jan 2019).
@@ -116,8 +120,8 @@
   (#894).
 
 * purrr now uses the base pipe (`|>`) and anonymous function short hand (`\(x)`),
-  in all examples. This means that examples will no longer work in R 4.0 and 
-  earlier so in those versions of R, the examples are automatically converted 
+  in all examples. This means that examples will no longer work in R 4.0 and
+  earlier so in those versions of R, the examples are automatically converted
   to a regular section with a note that they might not work (#936).
 
 * When map functions fail, they now report the element they failed at (#945).
@@ -135,17 +139,17 @@
 * New `list_transpose()` which automatically simplifies if possible (#875).
 
 * `accumulate()` and `accumulate2()` now both simplify the output if possible
-  using vctrs. New arguments `simplify` and `ptype` allow you to control the 
+  using vctrs. New arguments `simplify` and `ptype` allow you to control the
   details of simplification (#774, #809).
 
-* `flatten()` and friends are superseded in favour of `list_flatten()`, 
+* `flatten()` and friends are superseded in favour of `list_flatten()`,
   `list_c()`, `list_cbind()`, and `list_rbind()`.
 
-* `*_dfc()` and `*_dfr()` have been superseded in favour of using the 
+* `*_dfc()` and `*_dfr()` have been superseded in favour of using the
   appropriate map function along with `list_rbind()` or `list_cbind()` (#912).
 
 * `simplify()`, `simplify_all()`, and `as_vector()` have been superseded in
-  favour of `list_simplify()`. It provides a more consistent definition of 
+  favour of `list_simplify()`. It provides a more consistent definition of
   simplification (#900).
 
 * `transpose()` has been superseded in favour of `list_transpose()` (#875).
@@ -155,16 +159,16 @@
 
 * `_lgl()`, `_int()`, `_int()`, and `_dbl()` now use the same (strict) coercion
   methods as vctrs (#904). This means that:
-  
-    * `map_chr(TRUE, identity)`, `map_chr(0L, identity)`, and 
-      `map_chr(1L, identity)` are deprecated because we now believe that 
-      converting a logical/integer/double to a character vector should require 
+
+    * `map_chr(TRUE, identity)`, `map_chr(0L, identity)`, and
+      `map_chr(1L, identity)` are deprecated because we now believe that
+      converting a logical/integer/double to a character vector should require
       an explicit coercion.
-      
-    * `map_int(1.5, identity)` now fails because we believe that silently 
-      truncating doubles to integers is dangerous. But note that 
+
+    * `map_int(1.5, identity)` now fails because we believe that silently
+      truncating doubles to integers is dangerous. But note that
       `map_int(1, identity)` still works since no numeric precision is lost.
-      
+
     * `map_int(c(TRUE, FALSE), identity)`, `map_dbl(c(TRUE, FALSE), identity)`,
       `map_lgl(c(1L, 0L), identity)` and `map_lgl(c(1, 0), identity)` now
       succeed because 1/TRUE and 0/FALSE should be interchangeable.
@@ -185,7 +189,7 @@
 * `vec_depth()` is now `pluck_depth()` and works with more types of input
   (#818).
 
-* `pluck()` now requires indices to be length 1 (#813). It also now reports 
+* `pluck()` now requires indices to be length 1 (#813). It also now reports
   the correct type if you supply an unexpected index.
 
 * `pluck()` now accepts negative integers, indexing from the right (#603).
@@ -213,7 +217,7 @@
 * New `list_assign()` which is similar to `list_modify()` but doesn't work
   recursively (#822).
 
-* `list_modify()` no longer recurses into data frames (and other objects built 
+* `list_modify()` no longer recurses into data frames (and other objects built
   on top of lists that are fundamentally non-list like) (#810). You can
   revert to the previous behaviour by setting `.is_node = is.list`.
 
@@ -227,8 +231,8 @@
 * `modify_depth()` is no longer a generic. This makes it more consistent
   with `map_depth()`.
 
-* `map_depth()` and `modify_depth()` have a new `is_node` argument that 
-  allows you to control what counts as a level. The default uses 
+* `map_depth()` and `modify_depth()` have a new `is_node` argument that
+  allows you to control what counts as a level. The default uses
   `vec_is_list()` to avoid recursing into rich S3 objects like linear models
   or data.frames (#958, #920).
 
@@ -239,9 +243,9 @@
 
 * `possibly()` now defaults `otherwise` to NULL.
 
-* `modify_if(.else)` is now actually evaluated for atomic vectors (@mgirlich, 
+* `modify_if(.else)` is now actually evaluated for atomic vectors (@mgirlich,
   #701).
-   
+
 * `lmap_if()` correctly handles `.else` functions (#847).
 
 * `every()` now correctly propagates missing values using the same

R/imap.R

@@ -56,6 +56,13 @@ imap_dbl <- function(.x, .f, ...) {
   map2_dbl(.x, vec_index(.x), .f, ...)
 }
 
+#' @rdname imap
+#' @export
+imap_vec <- function(.x, .f, ...) {
+  .f <- as_mapper(.f, ...)
+  map2_vec(.x, vec_index(.x), .f, ...)
+}
+
 
 #' @export
 #' @rdname imap

R/list-simplify.R

@@ -7,9 +7,9 @@
 #' [list_flatten()].
 #'
 #' @param x A list.
-#' @param strict What should happen if simplification fails? If `TRUE`,
-#'   it will error. If `FALSE` and `ptype` is not supplied, it will return `x`
-#'   unchanged.
+#' @param strict What should happen if simplification fails? If `TRUE`
+#'   (the default) it will error. If `FALSE` and `ptype` is not supplied, 
+#'   it will return `x` unchanged.
 #' @param ptype An optional prototype to ensure that the output type is always
 #'   the same.
 #' @inheritParams rlang::args_dots_empty

R/list-transpose.R

@@ -14,9 +14,9 @@
 #' @param x A list of vectors to transpose.
 #' @param template A "template" that describes the output list. Can either be
 #'   a character vector (where elements are extracted by name), or an integer
-#'   vector (where elements are extracted by position). Defaults to the names
-#'   of the first element of `x`, or if they're not present, the integer
-#'   indices.
+#'   vector (where elements are extracted by position). Defaults to the union
+#'   of the names of the elements of `x`, or if they're not present, the
+#'   union of the integer indices.
 #' @param simplify Should the result be [simplified][list_simplify]?
 #'   * `TRUE`: simplify or die trying.
 #'   * `NA`: simplify if possible.
@@ -69,13 +69,25 @@ list_transpose <- function(x,
                            simplify = NA,
                            ptype = NULL,
                            default = NULL) {
-  vec_check_list(x)
+
+  check_list(x)
   check_dots_empty()
 
   if (length(x) == 0) {
     template <- integer()
-  } else {
-    template <- template %||% vec_index(x[[1]])
+  } else if (is.null(template)) {
+    indexes <- map(x, vec_index)
+    call <- current_env()
+    withCallingHandlers(
+      template <- reduce(indexes, vec_set_union),
+      vctrs_error_ptype2 = function(e) {
+        cli::cli_abort(
+          "Can't combine named and unnamed vectors.",
+          arg = template,
+          call = call
+        )
+      }
+    )
   }
 
   if (!is.character(template) && !is.numeric(template)) {

R/pmap.R

@@ -23,7 +23,25 @@
 #'   * A formula, e.g. `~ ..1 + ..2 / ..3`. This syntax is not recommended as
 #'     you can only refer to arguments by position.
 #' @inheritParams map
-#' @inherit map return
+#' @returns
+#' The output length is determined by the maximum length of all elements of `.l`.
+#' The output names are determined by the names of the first element of `.l`.
+#' The output type is determined by the suffix:
+#'
+#' * No suffix: a list; `.f()` can return anything.
+#'
+#' * `_lgl()`, `_int()`, `_dbl()`, `_chr()` return a logical, integer, double,
+#'   or character vector respectively; `.f()` must return a compatible atomic
+#'   vector of length 1.
+#'
+#' * `_vec()` return an atomic or S3 vector, the same type that `.f` returns.
+#'   `.f` can return pretty much any type of vector, as long as it is length 1.
+#'
+#' * `pwalk()` returns the input `.l` (invisibly). This makes it easy to
+#'    use in a pipe. The return value of `.f()` is ignored.
+#'
+#' Any errors thrown by `.f` will be wrapped in an error with class
+#' [purrr_error_indexed].
 #' @family map variants
 #' @export
 #' @examples

R/reduce.R

@@ -8,7 +8,22 @@
 #' `f` over `1:3` computes the value `f(f(1, 2), 3)`.
 #'
 #' @inheritParams map
-#' @param .y For `reduce2()` and `accumulate2()`, an additional
+#' @param ... Additional arguments passed on to the reduce function.
+#'
+#'   We now generally recommend against using `...` to pass additional
+#'   (constant) arguments to `.f`. Instead use a shorthand anonymous function:
+#'
+#'   ```R
+#'   # Instead of
+#'   x |> reduce(f, 1, 2, collapse = ",")
+#'   # do:
+#'   x |> reduce(\(x, y) f(x, y, 1, 2, collapse = ","))
+#'   ```
+#'
+#'   This makes it easier to understand which arguments belong to which
+#'   function and will tend to yield better error messages.
+#'
+#' @param .y For `reduce2()` an additional
 #'   argument that is passed to `.f`. If `init` is not set, `.y`
 #'   should be 1 element shorter than `.x`.
 #' @param .f For `reduce()`, a 2-argument function. The function will be passed

R/superseded-map-df.R

@@ -41,6 +41,23 @@
 #'   map(\(mod) as.data.frame(t(as.matrix(coef(mod))))) |>
 #'   list_rbind()
 #'
+#' # for certain pathological inputs `map_dfr()` and `map_dfc()` actually
+#' # both combine the list by column
+#' df <- data.frame(
+#'   x = c(" 13", "  15 "),
+#'   y = c("  34",  " 67 ")
+#' )
+#'
+#' # Was:
+#' map_dfr(df, trimws)
+#' map_dfc(df, trimws)
+#'
+#' # But list_rbind()/list_cbind() fail because they require data frame inputs
+#' try(map(df, trimws) |> list_rbind())
+#'
+#' # Instead, use modify() to apply a function to each column of a data frame
+#' modify(df, trimws)
+#'
 #' # map2 ---------------------------------------------
 #'
 #' ex_fun <- function(arg1, arg2){