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<!-- @moduledoc -->
TypedStruct is a library for defining structs with a type without writing
boilerplate code.
**NOTE:** This is an active fork of the original
[typedstruct](https://github.com/ejpcmac/typed_struct) work by Jean-Philippe Cugnet, which seems
to be no longer maintained. This version adds type information to Erlang
records and makes the project compile under OTP-26 and later.
## Rationale
To define a struct in Elixir, you probably want to define three things:
* the struct itself, with default values,
* the list of enforced keys,
* its associated type.
It ends up in something like this:
```elixir
defmodule Person do
@moduledoc """
A struct representing a person.
"""
@enforce_keys [:name]
defstruct name: nil,
age: nil,
happy?: true,
phone: nil
@typedoc "A person"
@type t() :: %__MODULE__{
name: String.t(),
age: non_neg_integer() | nil,
happy?: boolean(),
phone: String.t() | nil
}
end
```
In the example above you can notice several points:
* the keys are present in both the `defstruct` and type definition,
* enforced keys must also be written in `@enforce_keys`,
* if a key has no default value and is not enforced, its type should be
nullable.
If you want to add a field in the struct, you must therefore:
* add the key with its default value in the `defstruct` list,
* add the key with its type in the type definition.
If the field is not optional, you should even add it to `@enforce_keys`. This is
way too much work for lazy people like me, and moreover it can be error-prone.
It would be way better if we could write something like this:
```elixir
defmodule Person do
@moduledoc """
A struct representing a person.
"""
use TypedStruct
typedstruct do
@typedoc "A person"
field :name, String.t(), enforce: true
field :age, non_neg_integer()
field :happy?, boolean(), default: true
field :phone, String.t()
end
end
```
## How do I use `TypedStruct`?
### Setup
To use TypedStruct in your project, add this to your Mix dependencies:
```elixir
{:typedstruct, "~> 0.6"}
```
If you do not plan to compile modules using TypedStruct at runtime, you can add
`runtime: false` to the dependency tuple as TypedStruct is only used at build
time.
If you want to avoid `mix format` putting parentheses on field definitions,
you can add to your `.formatter.exs`:
```elixir
[
...,
import_deps: [:typedstruct]
]
```
### General usage
To define a typed struct, use
[`TypedStruct`](https://hexdocs.pm/typedstruct/TypedStruct.html), then define
your struct within a `typedstruct` block:
```elixir
defmodule MyStruct do
# Use TypedStruct to import the typedstruct macro.
use TypedStruct
# Define your struct.
typedstruct do
# Define each field with the field macro.
field :a_string, String.t()
# You can set a default value.
field :string_with_default, String.t(), default: "default"
# You can enforce a field.
field :enforced_field, integer(), enforce: true
end
end
```
Each field is defined through the
[`field/2`](https://hexdocs.pm/typedstruct/TypedStruct.html#field/2) macro.
To define a record use the `typedrecord` block:
```elixir
defmodule Person do
use TypedStruct
typedrecord :person do
@typedoc "A person"
field :name, String.t(),
field :age, non_neg_integer(), default: 0
end
end
```
### Options
All options are listed together here for quick reference.
Top-level options available on both `typedstruct` and `typedrecord`:
* `module: ModuleName` - defines the generated struct/record in a submodule.
* `visibility: :public | :private | :opaque` - controls generated type visibility.
* `strict: true` - requires each field to be enforced or provide `default` / `default_fn`.
* `constructors: true` - generates validated constructors.
* `introspection: true` - generates helper functions for fields, defaults,
required fields, and types (see [Introspection helpers](#introspection-helpers)).
* `docs: :full | :module_only | :fields_only | false` - controls how field docs
are merged into module documentation.
Additional `typedstruct`-only options:
* `enforce: true` - enforces all fields by default unless overridden per field.
* `new: true` - generates a simple `new/1` constructor (`struct(__MODULE__, attrs)`).
* `derive: [Protocol1, Protocol2]` - passes through `@derive` before `defstruct`.
* `opaque: true` - deprecated alias for `visibility: :opaque`.
Additional `typedrecord`-only options:
* `tag: atom()` - sets record tag passed to `Record.defrecord/3`.
* `opaque: true` - deprecated alias for `visibility: :opaque`.
Field-level options (`field/3`):
* `default: value` - static default value.
* `default_fn: &Mod.fun/0` - dynamic default used by generated constructors.
(`default` and `default_fn` are mutually exclusive.)
* `enforce: true | false` - field-level enforce override.
* `doc: "..."` - field-level documentation included in generated docs.
Examples
Enforce all keys by default:
```elixir
defmodule MyStruct do
use TypedStruct
# Enforce keys by default.
typedstruct enforce: true do
# This key is enforced.
field :enforced_by_default, term()
# You can override the default behaviour.
field :not_enforced, term(), enforce: false
# A key with a default value is not enforced.
field :not_enforced_either, integer(), default: 1
end
end
```
Generate opaque/private types with `visibility`:
```elixir
defmodule MyOpaqueStruct do
use TypedStruct
# Generate an opaque type for the struct.
typedstruct visibility: :opaque do
field :name, String.t()
end
end
```
Define generated code in a submodule:
```elixir
defmodule MyPrivateStruct do
use TypedStruct
# Generate a private type for the struct.
typedstruct visibility: :private do
field :name, String.t()
end
end
```
```elixir
defmodule MyModule do
use TypedStruct
# You now have %MyModule.Struct{}.
typedstruct module: Struct do
field :field, term()
end
end
```
#### Introspection helpers
When `introspection: true` is enabled, TypedStruct generates reflection helpers
at compile time.
For `typedstruct`, the following functions are generated on the struct module:
* `__fields__/0` - ordered list of field names.
* `__required__/0` - ordered list of enforced field names.
* `__defaults__/0` - map of static defaults from `default:`.
* `__dynamic_defaults__/0` - ordered list of fields using `default_fn:`.
* `__types__/0` - internal list used to build the generated typespec.
Example:
```elixir
defmodule User do
use TypedStruct
typedstruct introspection: true do
field :id, integer(), enforce: true
field :name, String.t(), default: "anonymous"
field :token, String.t(), default_fn: &UserDefaults.token/0
end
end
User.__fields__()
# => [:id, :name, :token]
User.__required__()
# => [:id]
User.__defaults__()
# => %{id: nil, name: "anonymous", token: nil}
User.__dynamic_defaults__()
# => [:token]
```
For `typedrecord :person`, the same information is exposed with record-prefixed
function names to avoid collisions when multiple records are defined in one
module:
* `person_fields/0`
* `person_required/0`
* `person_defaults/0`
* `person_dynamic_defaults/0`
* `person_types/0`
Example:
```elixir
defmodule People do
use TypedStruct
typedrecord :person, introspection: true do
field :id, integer(), enforce: true
field :name, String.t(), default: "anonymous"
end
end
People.person_fields()
# => [:id, :name]
```
These helpers are intended for tooling, schema inspection, and diagnostics.
If you need runtime validation/construction as well, combine with
`constructors: true`.
### Documentation
TypedStruct supports comprehensive documentation through multiple attributes:
#### Type Documentation with @typedoc
Add a `@typedoc` attribute in the `typedstruct` block to document the type:
```elixir
typedstruct do
@typedoc "A typed struct"
field :a_string, String.t()
field :an_int, integer()
end
```
#### Module Documentation
You can also document the entire module and submodules:
```elixir
typedstruct module: MyStruct do
@moduledoc "A submodule with a typed struct."
@typedoc "A typed struct in a submodule"
field :a_string, String.t()
field :an_int, integer()
end
```
#### Field Documentation
Document individual fields in two ways:
**1. Using the `doc:` option:**
```elixir
typedstruct do
field :a_string, String.t(), doc: "A string field"
field :an_int, integer(), doc: "An integer field"
end
```
**2. Using the `@doc` attribute (applies to the next field):**
```elixir
typedstruct do
@doc "A string field"
field :a_string, String.t()
@doc "An integer field"
field :an_int, integer()
end
```
The `@doc` attribute is automatically cleared after each field, ensuring it only documents the intended field. This approach is useful when you want to keep documentation close to the field definition.
TypedStruct will append a generated `## Fields` section to the module documentation when running `mix docs` for both `typedstruct` and `typedrecord` blocks:
```elixir
defmodule User do
use TypedStruct
@moduledoc "Represents an account user."
typedstruct do
field :name, String.t(), doc: "Display name shown in the UI."
field :email, String.t(), doc: "Primary email address."
field :active, boolean()
end
end
```
Only fields with a `doc` value are included in the generated `## Fields`
section.
You can combine docs and constructors options, for example:
```elixir
defmodule User do
use TypedStruct
typedstruct constructors: true, strict: true, introspection: true do
field :id, integer(), enforce: true, doc: "User id"
field :name, String.t(), default: "anonymous", doc: "Display name"
field :token, String.t(), default_fn: &UserDefaults.token/0
end
end
```
## Plugins
It is possible to extend the scope of TypedStruct by using its plugin interface,
as described in
[`TypedStruct.Plugin`](https://hexdocs.pm/typedstruct/TypedStruct.Plugin.html).
For instance, to automatically generate lenses with the
[Lens](https://github.com/obrok/lens) library, you can use
[`TypedStructLens`](https://github.com/saleyn/typedstruct_lens) and do:
```elixir
defmodule MyStruct do
use TypedStruct
typedstruct do
plugin TypedStructLens
field :a_field, String.t()
field :other_field, atom()
end
@spec change(t()) :: t()
def change(data) do
# a_field/0 is generated by TypedStructLens.
lens = a_field()
put_in(data, [lens], "Changed")
end
end
```
Presently plugins are not supported by the `typedrecord` block.
#### Default Plugins
You can specify default plugins when using TypedStruct, which will be automatically
injected into all `typedstruct` and `typedrecord` definitions. This is useful for
creating wrapper modules that provide preset plugins:
```elixir
defmodule MyApp.Type do
defmacro __using__(_) do
quote do
use TypedStruct, plugins: [MyApp.TypedStruct.Plugin.EctoTypes]
end
end
end
defmodule MyApp.User do
use MyApp.Type
typedstruct do
field :id, integer(), enforce: true
field :name, String.t(), ecto_type: :string
end
end
```
Now `MyApp.User` automatically has the `EctoTypes` plugin injected without needing
to manually call `plugin MyApp.TypedStruct.Plugin.EctoTypes` in the `typedstruct` block.
### Ecto Integration
TypedStruct provides optional integration with Ecto through the `TypedStruct.Ecto` module, enabling you to define Ecto schemas with automatic type inference:
```elixir
defmodule User do
use TypedStruct.Ecto
typedschema "users" do
field :id, :id
field :email, :string, enforce: true
field :name, :string
field :age, :integer
belongs_to :company, Company
has_many :posts, Post
timestamps()
end
end
```
The `typedschema` macro automatically infers Elixir types from Ecto field types, generates proper types for associations, supports polymorphic embeds, and enables type overrides with `::` syntax.
**For comprehensive guide with examples, see [ecto.md](ecto.md):**
- Field types and associations
- Embedded and polymorphic schemas
- Type overrides and custom types
- Real-world examples (e-commerce, CMS, notifications)
- Validation patterns
- Comparison with [typed_ecto_schema](https://hex.pm/packages/typed_ecto_schema)
### Built-in Integrations
* `TypedStruct.Ecto` – Optional module providing `typedschema/2` macro for seamless
Ecto schema integration. Requires Ecto to be installed.
* `TypedStruct.Plugin.EctoSchema` – Reference plugin showing how to build plugins for
external libraries.
### Third-party Plugins
* [`typedstruct_lens`](https://github.com/saleyn/typedstruct_lens) –
Integration with the [Lens](https://github.com/obrok/lens) library.
* [`typedstruct_legacy_reflection`](https://github.com/saleyn/typedstruct_legacy_reflection)
– Re-enables the legacy reflection functions from TypedStruct 0.1.x.
* [`typed_struct_ctor`](https://hexdocs.pm/typed_struct_ctor/TypedStructCtor.html)
– Adds validating (`new` and `from`) constructor functions.
> Try the macro out in real time without having to install or write any of your own code.
> All you need is a running instance of [Livebook](https://livebook.dev/)
>
> [](https://livebook.dev/run?url=https://github.com/withbelay/typed_struct_ctor/blob/main/try_it_out.livemd)
* [`typed_ecto_schema`](https://hex.pm/packages/typed_ecto_schema) –
Specialized library for Ecto schemas with automatic typespec generation for associations,
timestamps, and other Ecto-specific features.
This list is not meant to be exhaustive, please [search for “typedstruct” on
hex.pm](https://hex.pm/packages?search=typedstruct) for other results. If you
want your plugin to appear here, please open an issue.
## What do I get?
When defining an empty `typedstruct` block:
```elixir
defmodule Example do
use TypedStruct
typedstruct do
end
end
```
you get an empty struct with its module type `t()`:
```elixir
defmodule Example do
@enforce_keys []
defstruct []
@type t() :: %__MODULE__{}
end
```
Each `field` call adds information to the struct, `@enforce_keys` and the type
`t()`.
A field with no options adds the name to the `defstruct` list, with `nil` as
default. The type itself is made nullable:
```elixir
defmodule Example do
use TypedStruct
typedstruct do
field :name, String.t()
end
end
```
becomes:
```elixir
defmodule Example do
@enforce_keys []
defstruct name: nil
@type t() :: %__MODULE__{
name: String.t() | nil
}
end
```
The `default` option adds the default value to the `defstruct`:
```elixir
field :name, String.t(), default: "John Smith"
# Becomes
defstruct name: "John Smith"
```
When set to `true`, the `enforce` option enforces the key by adding it to the
`@enforce_keys` attribute.
```elixir
field :name, String.t(), enforce: true
# Becomes
@enforce_keys [:name]
defstruct name: nil
```
In both cases, the type has no reason to be nullable anymore by default. In one
case the field is filled with its default value and not `nil`, and in the other
case it is enforced. Both options would generate the following type:
```elixir
@type t() :: %__MODULE__{
name: String.t() # Not nullable
}
```
Passing `opaque: true` replaces `@type` with `@opaque` in the struct type
specification:
```elixir
typedstruct opaque: true do
field :name, String.t()
end
```
generates the following type:
```elixir
@opaque t() :: %__MODULE__{
name: String.t()
}
```
When passing `module: ModuleName`, the whole `typedstruct` block is wrapped in a
module definition. This way, the following definition:
```elixir
defmodule MyModule do
use TypedStruct
typedstruct module: Struct do
field :field, term()
end
end
```
becomes:
```elixir
defmodule MyModule do
defmodule Struct do
@enforce_keys []
defstruct field: nil
@type t() :: %__MODULE__{
field: term() | nil
}
end
end
```
To define a typed record, the following definition of the `typedrecord`:
```elixir
defmodule Person do
use TypedStruct
typedrecord :person do
@typedoc "A person"
field :name, String.t()
field :age, non_neg_integer(), default: 0
end
end
```
becomes:
```elixir
defmodule Person do
use Record
Record.defrecord(:person, name: nil, age: 0)
@type person :: {:person, String.t()|nil, non_neg_integer()}
end
```
## Usage
### General usage
To define a typed struct, use
[`TypedStruct`](https://hexdocs.pm/typedstruct/TypedStruct.html), then define
your struct within a `typedstruct` block:
```elixir
defmodule MyStruct do
# Use TypedStruct to import the typedstruct macro.
use TypedStruct
# Define your struct.
typedstruct do
# Define each field with the field macro.
field :a_string, String.t()
# You can set a default value.
field :string_with_default, String.t(), default: "default"
# You can enforce a field.
field :enforced_field, integer(), enforce: true
end
end
```
Each field is defined through the
[`field/2`](https://hexdocs.pm/typedstruct/TypedStruct.html#field/2) macro.
To define a record use the `typedrecord` block:
```elixir
defmodule Person do
use TypedStruct
typedrecord :person do
@typedoc "A person"
field :name, String.t(),
field :age, non_neg_integer(), default: 0
end
end
```
## Options
All options are listed together here for quick reference.
Top-level options available on both `typedstruct` and `typedrecord`:
* `module: ModuleName` - defines the generated struct/record in a submodule.
* `visibility: :public | :private | :opaque` - controls generated type visibility.
* `strict: true` - requires each field to be enforced or provide `default` / `default_fn`.
* `constructors: true` - generates validated constructors.
* `introspection: true` - generates helper functions for fields, defaults,
required fields, and types (see [Introspection helpers](#introspection-helpers)).
* `docs: :full | :module_only | :fields_only | false` - controls how field docs
are merged into module documentation.
Additional `typedstruct`-only options:
* `enforce: true` - enforces all fields by default unless overridden per field.
* `new: true` - generates a simple `new/1` constructor (`struct(__MODULE__, attrs)`).
* `derive: [Protocol1, Protocol2]` - passes through `@derive` before `defstruct`.
* `opaque: true` - deprecated alias for `visibility: :opaque`.
Additional `typedrecord`-only options:
* `tag: atom()` - sets record tag passed to `Record.defrecord/3`.
* `opaque: true` - deprecated alias for `visibility: :opaque`.
Field-level options (`field/3`):
* `default: value` - static default value.
* `default_fn: &Mod.fun/0` - dynamic default used by generated constructors.
(`default` and `default_fn` are mutually exclusive.)
* `enforce: true | false` - field-level enforce override.
* `doc: "..."` - field-level documentation included in generated docs.
Examples
Enforce all keys by default:
```elixir
defmodule MyStruct do
use TypedStruct
# Enforce keys by default.
typedstruct enforce: true do
# This key is enforced.
field :enforced_by_default, term()
# You can override the default behaviour.
field :not_enforced, term(), enforce: false
# A key with a default value is not enforced.
field :not_enforced_either, integer(), default: 1
end
end
```
Generate opaque/private types with `visibility`:
```elixir
defmodule MyOpaqueStruct do
use TypedStruct
# Generate an opaque type for the struct.
typedstruct visibility: :opaque do
field :name, String.t()
end
end
```
Define generated code in a submodule:
```elixir
defmodule MyPrivateStruct do
use TypedStruct
# Generate a private type for the struct.
typedstruct visibility: :private do
field :name, String.t()
end
end
```
```elixir
defmodule MyModule do
use TypedStruct
# You now have %MyModule.Struct{}.
typedstruct module: Struct do
field :field, term()
end
end
```
### Introspection helpers
When `introspection: true` is enabled, TypedStruct generates reflection helpers
at compile time.
For `typedstruct`, the following functions are generated on the struct module:
* `__fields__/0` - ordered list of field names.
* `__required__/0` - ordered list of enforced field names.
* `__defaults__/0` - map of static defaults from `default:`.
* `__dynamic_defaults__/0` - ordered list of fields using `default_fn:`.
* `__types__/0` - internal list used to build the generated typespec.
Example:
```elixir
defmodule User do
use TypedStruct
typedstruct introspection: true do
field :id, integer(), enforce: true
field :name, String.t(), default: "anonymous"
field :token, String.t(), default_fn: &UserDefaults.token/0
end
end
User.__fields__()
# => [:id, :name, :token]
User.__required__()
# => [:id]
User.__defaults__()
# => %{id: nil, name: "anonymous", token: nil}
User.__dynamic_defaults__()
# => [:token]
```
For `typedrecord :person`, the same information is exposed with record-prefixed
function names to avoid collisions when multiple records are defined in one
module:
* `person_fields/0`
* `person_required/0`
* `person_defaults/0`
* `person_dynamic_defaults/0`
* `person_types/0`
Example:
```elixir
defmodule People do
use TypedStruct
typedrecord :person, introspection: true do
field :id, integer(), enforce: true
field :name, String.t(), default: "anonymous"
end
end
People.person_fields()
# => [:id, :name]
```
These helpers are intended for tooling, schema inspection, and diagnostics.
If you need runtime validation/construction as well, combine with
`constructors: true`.
### Documentation
TypedStruct supports comprehensive documentation through multiple attributes:
#### Type Documentation with @typedoc
Add a `@typedoc` attribute in the `typedstruct` block to document the type:
```elixir
typedstruct do
@typedoc "A typed struct"
field :a_string, String.t()
field :an_int, integer()
end
```
#### Module Documentation
You can also document the entire module and submodules:
```elixir
typedstruct module: MyStruct do
@moduledoc "A submodule with a typed struct."
@typedoc "A typed struct in a submodule"
field :a_string, String.t()
field :an_int, integer()
end
```
#### Field Documentation
Document individual fields in two ways:
**1. Using the `doc:` option:**
```elixir
typedstruct do
field :a_string, String.t(), doc: "A string field"
field :an_int, integer(), doc: "An integer field"
end
```
**2. Using the `@doc` attribute (applies to the next field):**
```elixir
typedstruct do
@doc "A string field"
field :a_string, String.t()
@doc "An integer field"
field :an_int, integer()
end
```
The `@doc` attribute is automatically cleared after each field, ensuring it only documents the intended field. This approach is useful when you want to keep documentation close to the field definition.
`TypedStruct` will append a generated `## Fields` section to the module documentation when running `mix docs` for both `typedstruct` and `typedrecord` blocks:
```elixir
defmodule User do
use TypedStruct
@moduledoc "Represents an account user."
typedstruct do
field :name, String.t(), doc: "Display name shown in the UI."
field :email, String.t(), doc: "Primary email address."
field :active, boolean()
end
end
```
Only fields with a `doc` value are included in the generated `## Fields`
section.
You can combine docs and constructors options, for example:
```elixir
defmodule User do
use TypedStruct
typedstruct constructors: true, strict: true, introspection: true do
field :id, integer(), enforce: true, doc: "User id"
field :name, String.t(), default: "anonymous", doc: "Display name"
field :token, String.t(), default_fn: &UserDefaults.token/0
end
end
```
## Plugins
It is possible to extend the scope of TypedStruct by using its plugin interface,
as described in
[`TypedStruct.Plugin`](https://hexdocs.pm/typedstruct/TypedStruct.Plugin.html).
For instance, to automatically generate lenses with the
[Lens](https://github.com/obrok/lens) library, you can use
[`TypedStructLens`](https://github.com/saleyn/typedstruct_lens) and do:
```elixir
defmodule MyStruct do
use TypedStruct
typedstruct do
plugin TypedStructLens
field :a_field, String.t()
field :other_field, atom()
end
@spec change(t()) :: t()
def change(data) do
# a_field/0 is generated by TypedStructLens.
lens = a_field()
put_in(data, [lens], "Changed")
end
end
```
Presently plugins are not supported by the `typedrecord` block.
### Default Plugins
You can specify default plugins when using TypedStruct, which will be automatically
injected into all `typedstruct` and `typedrecord` definitions. This is useful for
creating wrapper modules that provide preset plugins:
```elixir
defmodule MyApp.Type do
defmacro __using__(_) do
quote do
use TypedStruct, plugins: [MyApp.TypedStruct.Plugin.EctoTypes]
end
end
end
defmodule MyApp.User do
use MyApp.Type
typedstruct do
field :id, integer(), enforce: true
field :name, String.t(), ecto_type: :string
end
end
```
Now `MyApp.User` automatically has the `EctoTypes` plugin injected without needing
to manually call `plugin MyApp.TypedStruct.Plugin.EctoTypes` in the `typedstruct` block.
### Third-party Plugins
* [`typedstruct_lens`](https://github.com/saleyn/typedstruct_lens) –
Integration with the [Lens](https://github.com/obrok/lens) library.
* [`typedstruct_legacy_reflection`](https://github.com/saleyn/typedstruct_legacy_reflection)
– Re-enables the legacy reflection functions from TypedStruct 0.1.x.
* [`typed_struct_ctor`](https://hexdocs.pm/typed_struct_ctor/TypedStructCtor.html)
– Adds validating (`new` and `from`) constructor functions.
> Try the macro out in real time without having to install or write any of your own code.
> All you need is a running instance of [Livebook](https://livebook.dev/)
>
> [](https://livebook.dev/run?url=https://github.com/withbelay/typed_struct_ctor/blob/main/try_it_out.livemd)
* [`typed_ecto_schema`](https://hex.pm/packages/typed_ecto_schema) –
Specialized library for Ecto schemas with automatic typespec generation for associations,
timestamps, and other Ecto-specific features.
This list is not meant to be exhaustive, please [search for “typedstruct” on
hex.pm](https://hex.pm/packages?search=typedstruct) for other results. If you
want your plugin to appear here, please open an issue.
## Ecto Integration
TypedStruct provides optional integration with Ecto through the `TypedStruct.Ecto` module, enabling you to define Ecto schemas with automatic type inference:
```elixir
defmodule User do
use TypedStruct.Ecto
typedschema "users" do
field :id, :id
field :email, :string, enforce: true
field :name, :string
field :age, :integer
belongs_to :company, Company
has_many :posts, Post
timestamps()
end
end
```
The `typedschema` macro automatically infers Elixir types from Ecto field types, generates proper types for associations, supports polymorphic embeds, and enables type overrides with `::` syntax.
**For comprehensive guide with examples, see [TypedStruct.Ecto Guide](ecto.md):**
- Field types and associations
- Embedded and polymorphic schemas
- Type overrides and custom types
- Real-world examples (e-commerce, CMS, notifications)
- Validation patterns
- Comparison with [typed_ecto_schema](https://hex.pm/packages/typed_ecto_schema)
### Built-in Integrations
* `TypedStruct.Ecto` – Optional module providing `typedschema/2` macro for seamless
Ecto schema integration. Requires Ecto to be installed.
* `TypedStruct.Plugin.EctoSchema` – Reference plugin showing how to build plugins for
external libraries.
<!-- @moduledoc -->
## Related libraries
* [Domo](https://github.com/IvanRublev/Domo): a library to validate structs that
define a `t()` type, like the one generated by `TypedStruct`.
* [TypedEctoSchema](https://github.com/bamorim/typed_ecto_schema): a library
that provides a DSL on top of `Ecto.Schema` to achieve the same result as
`TypedStruct`, with `Ecto`.
## [Contributing](CONTRIBUTING.md)
Before contributing to this project, please read the
[CONTRIBUTING.md](CONTRIBUTING.md).
## License
This project is licensed under the [MIT license](./LICENSE.md).