How to get the struct type in Elixir
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So you don’t know what’s the type of struct you’re passing somewhere? Maybe it can be one of few types and you have to distinguish them? Or any other reason… But it’s about checking the struct type. Just use one of the coolest Elixir features - pattern matching!
Check this out:
iex(1)> some_struct = %MyApp.User{}
iex(2)> %type{} = some_struct
iex(3)> type
MyApp.UserThat’s just a hook point for a bunch of cool facilities, like function call by module type:
defmodule Chess.Bishop do
def move(piece), do: move_diagonally(piece)
end
defmodule Chess.Rook do
def move(piece), do: move_straight(piece)
end
defmodule Chess.Pawn do
def move(piece), do: move_forward(piece)
endAnd then in console:
iex(1)> piece = get_chess_piece()
iex(2)> %module{} = piece
iex(3)> module.move(piece)Have fun! If you'd like to learn more about structs in Elixir, check this blog post: Elixir Trickery: Cheating on Structs, And Why It Pays Off.
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