# `MAVLink2.Dialect.XML`
[🔗](https://github.com/isaiahdw/mavlink2/blob/v0.1.0/lib/mavlink2/dialect/xml.ex#L1)

A `MAVLink2.Dialect` generated at compile time from a MAVLink XML file
and its includes:

    defmodule MyDialect do
      use MAVLink2.Dialect.XML, file: "priv/my_dialect.xml"
    end

`:file` is relative to the project root, or absolute. The module
recompiles when any of the XML files changes.

Generated in the dialect module:

| Function | |
| --- | --- |
| `crc_extra/1`, `payload_length/1`, `target_offsets/1` | the `MAVLink2.Dialect` callbacks; `target_offsets/1` is `{nil, nil}` for an unknown id |
| `msgids/0`, `message/1` | every message id; the struct module for an id, or `nil` |
| `encode/1` | a message struct to `{msgid, payload}` (untruncated; `MAVLink2.Frame` truncates); `ArgumentError` for an integer outside its field's type |
| `decode/2` | `{msgid, payload}` to `{:ok, struct}`, or `{:error, {:unknown_msgid, id}}` |
| `enum/1`, `enum_value/2`, `enum_entry/2` | an enum as `%{entry => value}`, an entry's value, a value's entry |

And a module per message, named from the message (`COMMAND_LONG` is
`MyDialect.CommandLong`): a struct with the XML's field names as written, each
starting at its zero value (`MAVLink2.Codec`), and `msgid/0`,
`crc_extra/0`, `layout/0`, `target_offsets/0`. A `uint8_t_mavlink_version` field starts at
the XML's `<version>`. Enum and entry names are lowercase atoms
(`:mav_cmd`, `:mav_cmd_component_arm_disarm`).

---

*Consult [api-reference.md](api-reference.md) for complete listing*