timteafan / loopurrr

Translate purrr functions into regular for loops

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loopurrr's Issues

`as_loop` can't be used for debugging

When as_loop is used on a non-working call it throws an error. This behavior makes it impossible to use it as debugging tool.

Error when .f contains curly braces

map(1:4,  function(x) {
  x
  }) %>% as_loop()
#> Error: 'text' should either be length 1, or same length as 'ranges'

This error is probably raised in insert_and_reformat_text.

Remove `tryCatch` when `as_loop` is called with a map extractor function that uses names

We don't need tryCatch as long as .inp1 is a name.

It's only needed when .inp1 is an integer which might cause an out of bound error.

# --- convert: `map(l1, "a")` as loop --- #
.inp1 <- "a"
out <- vector("list", length = length(l1))

for (i in seq_along(l1)) {
  .tmp <- tryCatch({l1[[i]][[.inp1]]
  }, error = function(e) {})
  if (!is.null(.tmp)) out[[i]] <- .tmp
}
# --- end loop --- #

Add safety checks of `.f`

It is possible that the function in .f uses the same variable as specified in idx which defaults to i. There should be a check in place, checking this , raising an error with the advise to set idx to a variable that is not used in .f.

map(1:4,  function(x) {
  i <- 5
  x + i
  }) %>% as_loop()

Need to solve #6 before solving this issue.

There also be other safety checks in place for all possible inputs like .sel .inp1 etc.

Error: 'ranges' should be a list of 4-element integer vectors

Sometimes calls to as_loop through the following error:

Error: 'ranges' should be a list of 4-element integer vectors

It is not clear to me yet, when this happens. Rerunning the code often will resolve the error.

This is caused by the output function when in RStudio.

Need to give it a deeper look.

only `~.x` in `.f` not working

Find the reason why this is not working:

map(1:5, ~.x) %>% as_loop
#> Error in expr[[i]] : object of type 'symbol' is not subsettable

`as_loop()` doesn't work correctly on `pmap`

library(loopurrr)
#> Loading required package: purrr

x <- list(1, 1, 1)
y <- list(10, 20, 30)
z <- list(100, 200, 300)
a <- list(x, y, z)

# expected
pmap(a, sum)
#> [[1]]
#> [1] 111
#> 
#> [[2]]
#> [1] 221
#> 
#> [[3]]
#> [1] 331

# doesn't work
pmap(a, sum) %>% as_loop()
#> Error in !is_clipr: invalid argument type

# works!
pmap(list(x, y, z), sum) %>% as_loop()
#> Error in !is_clipr: invalid argument type

^{Created on 2022-10-05 by the reprex package (v0.3.0)}

add support for `map_depth`

Figure out how to make as_loop work with map_depth.

`for` loop produces different result as `map` due to lazy evaluation

R's lazy evaluation can lead to different results when translating map function calls to for loops. Below is one example that Claus Wilke provided on Twitter.

Lets think about, whether there is someway to force evaluation programmatically to produce the same result as map and if not, this needs to be mentioned an a vignette together with other caveats and quirks of as_loop().

library(loopurrr)
#> Loading required package: purrr

make_add <- function(n) {
  function(x) {
    x + n
  }
}

idx <- as.list(1:5)

z <- map(idx, make_add)

map(idx, make_add) %>% 
   as_loop()

# --- convert: `map(idx, make_add)` as loop --- #
out <- vector("list", length = length(idx))

for (i in seq_along(idx)) {
  out[[i]] <- make_add(idx[[i]])
}
# --- end loop --- #

z[[1]](10)
#> [1] 11
out[[1]](10)
#> [1] 15

^{Created on 2022-04-05 by the reprex package (v0.3.0)}