-module(gleam@pair).
-compile([no_auto_import, nowarn_unused_vars]).

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

-spec first({GJ, any()}) -> GJ.
first(Pair) ->
    {A, _} = Pair,
    A.

-spec second({any(), GM}) -> GM.
second(Pair) ->
    {_, A} = Pair,
    A.

-spec swap({GN, GO}) -> {GO, GN}.
swap(Pair) ->
    {A, B} = Pair,
    {B, A}.

-spec map_first({GP, GQ}, fun((GP) -> GR)) -> {GR, GQ}.
map_first(Pair, Fun) ->
    {A, B} = Pair,
    {Fun(A), B}.

-spec map_second({GS, GT}, fun((GT) -> GU)) -> {GS, GU}.
map_second(Pair, Fun) ->
    {A, B} = Pair,
    {A, Fun(B)}.

-spec new(GV, GW) -> {GV, GW}.
new(First, Second) ->
    {First, Second}.