-module(gleam@pair).
-compile(no_auto_import).

-export([first/1, second/1, swap/1, map_first/2, map_second/2]).

-spec first({CP, any()}) -> CP.
first(Pair) ->
    {A, _@1} = Pair,
    A.

-spec second({any(), CS}) -> CS.
second(Pair) ->
    {_@1, A} = Pair,
    A.

-spec swap({CT, CU}) -> {CU, CT}.
swap(Pair) ->
    {A, B} = Pair,
    {B, A}.

-spec map_first({CV, CW}, fun((CV) -> CX)) -> {CX, CW}.
map_first(Pair, Fun) ->
    {A, B} = Pair,
    {Fun(A), B}.

-spec map_second({CY, CZ}, fun((CZ) -> DA)) -> {CY, DA}.
map_second(Pair, Fun) ->
    {A, B} = Pair,
    {A, Fun(B)}.