189 lines
4.0 KiB
Erlang
189 lines
4.0 KiB
Erlang
-module(gleam@order).
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-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
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-define(FILEPATH, "src/gleam/order.gleam").
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-export([negate/1, to_int/1, compare/2, reverse/1, break_tie/2, lazy_break_tie/2]).
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-export_type([order/0]).
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-if(?OTP_RELEASE >= 27).
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-define(MODULEDOC(Str), -moduledoc(Str)).
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-define(DOC(Str), -doc(Str)).
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-else.
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-define(MODULEDOC(Str), -compile([])).
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-define(DOC(Str), -compile([])).
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-endif.
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-type order() :: lt | eq | gt.
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-file("src/gleam/order.gleam", 32).
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?DOC(
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" Inverts an order, so less-than becomes greater-than and greater-than\n"
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" becomes less-than.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert negate(Lt) == Gt\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert negate(Eq) == Eq\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert negate(Gt) == Lt\n"
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" ```\n"
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).
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-spec negate(order()) -> order().
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negate(Order) ->
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case Order of
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lt ->
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gt;
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eq ->
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eq;
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gt ->
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lt
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end.
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-file("src/gleam/order.gleam", 56).
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?DOC(
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" Produces a numeric representation of the order.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert to_int(Lt) == -1\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert to_int(Eq) == 0\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" assert to_int(Gt) == 1\n"
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" ```\n"
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).
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-spec to_int(order()) -> integer().
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to_int(Order) ->
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case Order of
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lt ->
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-1;
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eq ->
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0;
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gt ->
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1
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end.
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-file("src/gleam/order.gleam", 72).
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?DOC(
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" Compares two `Order` values to one another, producing a new `Order`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" assert compare(Eq, with: Lt) == Gt\n"
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" ```\n"
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).
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-spec compare(order(), order()) -> order().
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compare(A, B) ->
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case {A, B} of
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{X, Y} when X =:= Y ->
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eq;
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{lt, _} ->
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lt;
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{eq, gt} ->
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lt;
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{_, _} ->
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gt
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end.
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-file("src/gleam/order.gleam", 92).
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?DOC(
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" Inverts an ordering function, so less-than becomes greater-than and greater-than\n"
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" becomes less-than.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" import gleam/int\n"
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" import gleam/list\n"
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"\n"
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" assert list.sort([1, 5, 4], by: reverse(int.compare)) == [5, 4, 1]\n"
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" ```\n"
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).
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-spec reverse(fun((I, I) -> order())) -> fun((I, I) -> order()).
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reverse(Orderer) ->
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fun(A, B) -> Orderer(B, A) end.
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-file("src/gleam/order.gleam", 112).
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?DOC(
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" Return a fallback `Order` in case the first argument is `Eq`.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" import gleam/int\n"
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"\n"
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" assert break_tie(in: int.compare(1, 1), with: Lt) == Lt\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" import gleam/int\n"
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"\n"
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" assert break_tie(in: int.compare(1, 0), with: Eq) == Gt\n"
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" ```\n"
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).
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-spec break_tie(order(), order()) -> order().
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break_tie(Order, Other) ->
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case Order of
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lt ->
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Order;
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gt ->
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Order;
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eq ->
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Other
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end.
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-file("src/gleam/order.gleam", 139).
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?DOC(
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" Invokes a fallback function returning an `Order` in case the first argument\n"
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" is `Eq`.\n"
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"\n"
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" This can be useful when the fallback comparison might be expensive and it\n"
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" needs to be delayed until strictly necessary.\n"
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"\n"
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" ## Examples\n"
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"\n"
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" ```gleam\n"
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" import gleam/int\n"
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"\n"
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" assert lazy_break_tie(in: int.compare(1, 1), with: fn() { Lt }) == Lt\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" import gleam/int\n"
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"\n"
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" assert lazy_break_tie(in: int.compare(1, 0), with: fn() { Eq }) == Gt\n"
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" ```\n"
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).
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-spec lazy_break_tie(order(), fun(() -> order())) -> order().
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lazy_break_tie(Order, Comparison) ->
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case Order of
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lt ->
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Order;
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gt ->
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Order;
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eq ->
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Comparison()
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end.
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