如何获取字典中所有键的数组？

Question

如何在 Julia 中将字典的所有键作为单独的数组获取。

例如：

Dict("a" => 123, "b" => 456, "c" => 789)

将给出以下数组：

["a", "b", "c"]

Answer 1

以下是您可以这样做的方法（如果迭代器足以让您仅用于keys避免物化数组）：

julia> d = Dict("a" => 123, "b" => 456, "c" => 789)
Dict{String, Int64} with 3 entries:
  "c" => 789
  "b" => 456
  "a" => 123

julia> keys(d)
KeySet for a Dict{String, Int64} with 3 entries. Keys:
  "c"
  "b"
  "a"

julia> collect(keys(d))
3-element Vector{String}:
 "c"
 "b"
 "a"