keys

Array[P] keys(Map[P, Y])

Creates an Array of the keys from the input Map, in the same order as the elements in the map.

Parameters

1. Map[P, Y]: Map from which to extract keys.

Returns: Array[P] of the input Maps keys.

Example: test_keys.wdl

version 1.1

workflow test_keys {
  input {
    Map[String,Int] x = {"a": 1, "b": 2, "c": 3}
    Map[String, Pair[File, File]] str_to_files = {
      "a": ("data/questions.txt", "data/answers.txt"),
      "b": ("data/request.txt", "data/response.txt")
    }
  }

  scatter (item in as_pairs(str_to_files)) {
    String key = item.left
  }

  Array[String] str_to_files_keys = key
  Array[String] expected = ["a", "b", "c"]

  output {
    Boolean is_true1 = keys(x) == expected
    Boolean is_true2 = str_to_files_keys == keys(str_to_files)
  }
}

{}

{
  "test_keys.is_true1": true,
  "test_keys.is_true2": true
}