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| @@ -66,6 +66,8 @@ iex> N.mult(1.5, 100) | |
| 66 66 | Using Decimals: (requires the [Decimal](https://hex.pm/packages/decimal) library.) |
| 67 67 | |
| 68 68 | ```elixir |
| 69 | + iex> alias Numbers, as: N |
| 70 | + |
| 69 71 | iex> d = Decimal.new(2) |
| 70 72 | iex> N.div(d, 10) |
| 71 73 | #Decimal<0.2> |
| @@ -84,13 +86,14 @@ The package can be installed as: | |
| 84 86 | |
| 85 87 | ```elixir |
| 86 88 | def deps do |
| 87 | - [{:numbers, "~> 5.0.0"}] |
| 89 | + [{:numbers, "~> 5.0.1"}] |
| 88 90 | end |
| 89 91 | ``` |
| 90 92 | |
| 91 93 | ## Changelog |
| 92 94 | |
| 93 | - - 5.0.0 MAJOR OVERHAUL: New implementation based on a set of Protocols. Should be a lot faster and easier on implementers. Also uses a new method to perform coercions based on the `Coerce` library. |
| 95 | + - 5.0.1 Possibility to import overloaded operator variants. Also, greatly improved documentation. |
| 96 | + - 5.0.0 MAJOR OVERHAUL: New implementation based on a set of Protocols. Should be a lot faster and easier on implementers. Also uses a new method to perform coercions based on the `Coerce` library. [Announcement post](https://elixirforum.com/t/numbers-a-generic-wrapper-to-use-any-custom-numeric-type/2846/7) |
| 94 97 | - 4.0.0 Breaking change: Move `Numeric` to `Numbers.Numeric`, to follow proper code organization conventions. |
| 95 98 | - 3.0.1 Improved README |
| 96 99 | - 3.0.0 Remove public `Numbers.coerce/2` function, as it had confused naming and very limited use. Added optional `Numeric.coerce/2` callback (which works very different from the old `Numbers.coerce/2` function) which is now used underwater when coercion should happen. |
| @@ -7,9 +7,9 @@ | |
| 7 7 | [<<"lib/numbers.ex">>,<<"lib/numbers/helper.ex">>, |
| 8 8 | <<"lib/numbers/implementations/decimal.ex">>, |
| 9 9 | <<"lib/numbers/implementations/float.ex">>, |
| 10 | - <<"lib/numbers/implementations/integer.ex">>,<<"lib/numbers/protocols.ex">>, |
| 11 | - <<"lib/numbers_old.exs">>,<<"lib/numeric.exs">>,<<"mix.exs">>, |
| 12 | - <<"README.md">>,<<"LICENSE">>]}. |
| 10 | + <<"lib/numbers/implementations/integer.ex">>,<<"lib/numbers/operators.ex">>, |
| 11 | + <<"lib/numbers/protocols.ex">>,<<"lib/numbers_old.exs">>, |
| 12 | + <<"lib/numeric.exs">>,<<"mix.exs">>,<<"README.md">>,<<"LICENSE">>]}. |
| 13 13 | {<<"licenses">>,[<<"MIT">>]}. |
| 14 14 | {<<"links">>,[{<<"GitHub">>,<<"https://github.com/Qqwy/elixir_number/">>}]}. |
| 15 15 | {<<"maintainers">>,[<<"Wiebe-Marten Wijnja/Qqwy">>]}. |
| @@ -23,4 +23,4 @@ | |
| 23 23 | {<<"name">>,<<"decimal">>}, |
| 24 24 | {<<"optional">>,true}, |
| 25 25 | {<<"requirement">>,<<"~> 1.3.0">>}]]}. |
| 26 | - {<<"version">>,<<"5.0.0-rc0">>}. |
| 26 | + {<<"version">>,<<"5.0.1">>}. |
| @@ -1,4 +1,65 @@ | |
| 1 1 | defmodule Numbers do |
| 2 | + @moduledoc """ |
| 3 | + Allows you to use arithmetical operations on _any_ type |
| 4 | + that implements the proper protocols. |
| 5 | + |
| 6 | + For each arithmetical operation, a different protocol is used |
| 7 | + so that types for which only a subset of these operations makes sense |
| 8 | + can still work with those. |
| 9 | + |
| 10 | + ## Basic Usage |
| 11 | + |
| 12 | + Usually, `Numbers` is used in another module by using |
| 13 | + `alias Numbers, as: N`, followed by calling the functions using |
| 14 | + this aliased but still descriptive syntax: |
| 15 | + `total_price = N.mult(N.add(price, fee), vat)` |
| 16 | + |
| 17 | + Because `Numbers` dispatches based on protocol definitions, |
| 18 | + you only need to swap what kind of arguments are used |
| 19 | + to change the type of the result. |
| 20 | + |
| 21 | + |
| 22 | + ## Overloaded Operators |
| 23 | + |
| 24 | + As explicit opt-in functionality, `Numbers` will add overloaded |
| 25 | + operators to your module, if you write `use Numbers, overload_operators: true` |
| 26 | + |
| 27 | + This will alter `a + b`, `a - b`, `a * b`, `a / b`, `-a` and `abs(a)` to |
| 28 | + dispatch to the corresponding functions in the `Numbers` module. |
| 29 | + |
| 30 | + Do note that these overloaded operator versions are _not_ allowed in guard tests, |
| 31 | + which is why this functionality is only provided as an opt-in option to use |
| 32 | + when an algorithm would be too unreadable without it. |
| 33 | + |
| 34 | + |
| 35 | + ## Examples: |
| 36 | + |
| 37 | + Using built-in numbers: |
| 38 | + |
| 39 | + iex> alias Numbers, as: N |
| 40 | + iex> N.add(1, 2) |
| 41 | + 3 |
| 42 | + iex> N.mult(3,5) |
| 43 | + 15 |
| 44 | + iex> N.mult(1.5, 100) |
| 45 | + 150.0 |
| 46 | + |
| 47 | + Using Decimals: (requires the [Decimal](https://hex.pm/packages/decimal) library.) |
| 48 | + |
| 49 | + iex> alias Numbers, as: N |
| 50 | + iex> d = Decimal.new(2) |
| 51 | + iex> N.div(d, 10) |
| 52 | + #Decimal<0.2> |
| 53 | + iex> small_number = N.div(d, 1234) |
| 54 | + #Decimal<0.001620745542949756888168557536> |
| 55 | + iex> N.pow(small_number, 100) |
| 56 | + #Decimal<9.364478495445313580679473524E-280> |
| 57 | + |
| 58 | + ## Defining your own Numbers implementations |
| 59 | + |
| 60 | + See `Numbers.Protocols` for a full explanation on how to do this. |
| 61 | + """ |
| 62 | + |
| 2 63 | import Kernel, except: [div: 2] |
| 3 64 | |
| 4 65 | @type t :: any |
| @@ -91,4 +152,25 @@ defmodule Numbers do | |
| 91 152 | """ |
| 92 153 | @spec to_float(t) :: {:ok, t_as_float :: float} | :error |
| 93 154 | defdelegate to_float(num), to: Numbers.Protocols.ToFloat |
| 155 | + |
| 156 | + |
| 157 | + defmacro __using__(opts) do |
| 158 | + if opts[:overload_operators] != true do |
| 159 | + raise """ |
| 160 | + `use Numbers` called without `overload_operators: true` option. |
| 161 | + |
| 162 | + Either make the exporting of operators explicit by writing |
| 163 | + `use Numbers, overload_operators: true` |
| 164 | + or if you do not want the overridden operators, |
| 165 | + simply use Numbers directly, and optionally |
| 166 | + alias it, using: |
| 167 | + `alias Numbers, as: N`. |
| 168 | + """ |
| 169 | + else |
| 170 | + quote do |
| 171 | + import Kernel, except: [abs: 1, *: 2, /: 2, -: 2, -: 1, +: 2] |
| 172 | + import Numbers.Operators |
| 173 | + end |
| 174 | + end |
| 175 | + end |
| 94 176 | end |
| @@ -1,4 +1,9 @@ | |
| 1 1 | defmodule Numbers.Helper do |
| 2 | + @moduledoc """ |
| 3 | + Helper functions that might make the implementation |
| 4 | + of Numbers for your own numberlike types easier. |
| 5 | + """ |
| 6 | + |
| 2 7 | @doc """ |
| 3 8 | Performs 'Exponentiation by Squaring', |
| 4 9 | which is a reasonably fast algorithm to compute integer powers, |
| @@ -0,0 +1,15 @@ | |
| 1 | + defmodule Numbers.Operators do |
| 2 | + # Do not import this module directly. |
| 3 | + # Instead, use `use Numbers, override_operators: true` |
| 4 | + # which will import this module's functions properly. |
| 5 | + @moduledoc false |
| 6 | + |
| 7 | + defdelegate a + b, to: Numbers, as: :add |
| 8 | + defdelegate a - b, to: Numbers, as: :sub |
| 9 | + defdelegate a * b, to: Numbers, as: :mult |
| 10 | + defdelegate a / b, to: Numbers, as: :div |
| 11 | + defdelegate -a, to: Numbers, as: :minus |
| 12 | + defdelegate abs(a), to: Numbers, as: :abs |
| 13 | + |
| 14 | + defdelegate pow(a, b), to: Numbers |
| 15 | + end |
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