pmap.md
In purrr: Functional Programming Tools

verifies result types and length

Code
  pmap_int(list(1), ~"x")
Condition
  Error in `pmap_int()`:
  i In index: 1.
  Caused by error:
  ! Can't coerce from a string to an integer.
Code
  pmap_int(list(1), ~ 1:2)
Condition
  Error in `pmap_int()`:
  i In index: 1.
  Caused by error:
  ! Result must be length 1, not 2.
Code
  pmap_vec(list(1), ~1, .ptype = character())
Condition
  Error in `pmap_vec()`:
  ! Can't convert `<list>[[1]]` <double> to <character>.

requires list of vectors

Code
  pmap(environment(), identity)
Condition
  Error in `pmap()`:
  ! `.l` must be a list, not an environment.
Code
  pmap(list(environment()), identity)
Condition
  Error in `pmap()`:
  ! `.l[[1]]` must be a vector, not an environment.

recycles inputs

Code
  pmap(list(1:2, 1:3), `+`)
Condition
  Error in `pmap()`:
  ! Can't recycle `.l[[1]]` (size 2) to match `.l[[2]]` (size 3).
Code
  pmap(list(1:2, integer()), `+`)
Condition
  Error in `pmap()`:
  ! Can't recycle `.l[[1]]` (size 2) to match `.l[[2]]` (size 0).