352 lines
8.2 KiB
Erlang
352 lines
8.2 KiB
Erlang
-module(gleam@bool).
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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/bool.gleam").
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-export(['and'/2, 'or'/2, negate/1, nor/2, nand/2, exclusive_or/2, exclusive_nor/2, to_string/1, guard/3, lazy_guard/3]).
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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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?MODULEDOC(
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" A type with two possible values, `True` and `False`. Used to indicate whether\n"
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" things are... true or false!\n"
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"\n"
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" Often is it clearer and offers more type safety to define a custom type\n"
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" than to use `Bool`. For example, rather than having a `is_teacher: Bool`\n"
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" field consider having a `role: SchoolRole` field where `SchoolRole` is a custom\n"
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" type that can be either `Student` or `Teacher`.\n"
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).
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-file("src/gleam/bool.gleam", 31).
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?DOC(
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" Returns the and of two bools, but it evaluates both arguments.\n"
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"\n"
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" It's the function equivalent of the `&&` operator.\n"
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" This function is useful in higher order functions or pipes.\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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" and(True, True)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" and(False, True)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" False |> and(True)\n"
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" // -> False\n"
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" ```\n"
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).
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-spec 'and'(boolean(), boolean()) -> boolean().
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'and'(A, B) ->
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A andalso B.
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-file("src/gleam/bool.gleam", 57).
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?DOC(
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" Returns the or of two bools, but it evaluates both arguments.\n"
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"\n"
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" It's the function equivalent of the `||` operator.\n"
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" This function is useful in higher order functions or pipes.\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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" or(True, True)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" or(False, True)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" False |> or(True)\n"
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" // -> True\n"
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" ```\n"
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).
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-spec 'or'(boolean(), boolean()) -> boolean().
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'or'(A, B) ->
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A orelse B.
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-file("src/gleam/bool.gleam", 77).
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?DOC(
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" Returns the opposite bool value.\n"
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"\n"
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" This is the same as the `!` or `not` operators in some other languages.\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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" negate(True)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" negate(False)\n"
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" // -> True\n"
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" ```\n"
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).
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-spec negate(boolean()) -> boolean().
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negate(Bool) ->
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not Bool.
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-file("src/gleam/bool.gleam", 105).
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?DOC(
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" Returns the nor of two bools.\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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" nor(False, False)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nor(False, True)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nor(True, False)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nor(True, True)\n"
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" // -> False\n"
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" ```\n"
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).
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-spec nor(boolean(), boolean()) -> boolean().
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nor(A, B) ->
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not (A orelse B).
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-file("src/gleam/bool.gleam", 133).
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?DOC(
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" Returns the nand of two bools.\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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" nand(False, False)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nand(False, True)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nand(True, False)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" nand(True, True)\n"
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" // -> False\n"
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" ```\n"
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).
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-spec nand(boolean(), boolean()) -> boolean().
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nand(A, B) ->
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not (A andalso B).
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-file("src/gleam/bool.gleam", 161).
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?DOC(
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" Returns the exclusive or of two bools.\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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" exclusive_or(False, False)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_or(False, True)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_or(True, False)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_or(True, True)\n"
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" // -> False\n"
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" ```\n"
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).
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-spec exclusive_or(boolean(), boolean()) -> boolean().
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exclusive_or(A, B) ->
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A /= B.
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-file("src/gleam/bool.gleam", 189).
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?DOC(
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" Returns the exclusive nor of two bools.\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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" exclusive_nor(False, False)\n"
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" // -> True\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_nor(False, True)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_nor(True, False)\n"
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" // -> False\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" exclusive_nor(True, True)\n"
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" // -> True\n"
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" ```\n"
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).
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-spec exclusive_nor(boolean(), boolean()) -> boolean().
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exclusive_nor(A, B) ->
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A =:= B.
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-file("src/gleam/bool.gleam", 207).
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?DOC(
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" Returns a string representation of the given bool.\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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" to_string(True)\n"
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" // -> \"True\"\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" to_string(False)\n"
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" // -> \"False\"\n"
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" ```\n"
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).
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-spec to_string(boolean()) -> binary().
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to_string(Bool) ->
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case Bool of
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false ->
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<<"False"/utf8>>;
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true ->
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<<"True"/utf8>>
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end.
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-file("src/gleam/bool.gleam", 266).
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?DOC(
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" Run a callback function if the given bool is `False`, otherwise return a\n"
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" default value.\n"
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"\n"
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" With a `use` expression this function can simulate the early-return pattern\n"
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" found in some other programming languages.\n"
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"\n"
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" In a procedural language:\n"
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"\n"
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" ```js\n"
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" if (predicate) return value;\n"
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" // ...\n"
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" ```\n"
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"\n"
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" In Gleam with a `use` expression:\n"
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"\n"
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" ```gleam\n"
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" use <- guard(when: predicate, return: value)\n"
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" // ...\n"
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" ```\n"
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"\n"
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" Like everything in Gleam `use` is an expression, so it short circuits the\n"
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" current block, not the entire function. As a result you can assign the value\n"
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" to a variable:\n"
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"\n"
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" ```gleam\n"
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" let x = {\n"
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" use <- guard(when: predicate, return: value)\n"
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" // ...\n"
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" }\n"
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" ```\n"
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"\n"
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" Note that unlike in procedural languages the `return` value is evaluated\n"
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" even when the predicate is `False`, so it is advisable not to perform\n"
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" expensive computation nor side-effects there.\n"
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"\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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" let name = \"\"\n"
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" use <- guard(when: name == \"\", return: \"Welcome!\")\n"
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" \"Hello, \" <> name\n"
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" // -> \"Welcome!\"\n"
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" ```\n"
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"\n"
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" ```gleam\n"
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" let name = \"Kamaka\"\n"
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" use <- guard(when: name == \"\", return: \"Welcome!\")\n"
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" \"Hello, \" <> name\n"
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" // -> \"Hello, Kamaka\"\n"
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" ```\n"
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).
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-spec guard(boolean(), BSY, fun(() -> BSY)) -> BSY.
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guard(Requirement, Consequence, Alternative) ->
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case Requirement of
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true ->
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Consequence;
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false ->
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Alternative()
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end.
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-file("src/gleam/bool.gleam", 307).
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?DOC(
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" Runs a callback function if the given bool is `True`, otherwise runs an\n"
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" alternative callback function.\n"
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"\n"
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" Useful when further computation should be delayed regardless of the given\n"
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" bool's value.\n"
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"\n"
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" See [`guard`](#guard) for more info.\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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" let name = \"Kamaka\"\n"
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" let inquiry = fn() { \"How may we address you?\" }\n"
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" use <- lazy_guard(when: name == \"\", return: inquiry)\n"
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" \"Hello, \" <> name\n"
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" // -> \"Hello, Kamaka\"\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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" let name = \"\"\n"
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" let greeting = fn() { \"Hello, \" <> name }\n"
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" use <- lazy_guard(when: name == \"\", otherwise: greeting)\n"
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" let number = int.random(99)\n"
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" let name = \"User \" <> int.to_string(number)\n"
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" \"Welcome, \" <> name\n"
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" // -> \"Welcome, User 54\"\n"
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" ```\n"
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).
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-spec lazy_guard(boolean(), fun(() -> BSZ), fun(() -> BSZ)) -> BSZ.
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lazy_guard(Requirement, Consequence, Alternative) ->
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case Requirement of
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true ->
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Consequence();
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false ->
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Alternative()
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end.
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