Improve documentation

CHANGELOG.md

@@ -5,7 +5,8 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 ### Added
-- `parse_env` attribute which is using for parse env variable in arbitrary type
+- `parse_env` attribute for custom parsing of environment variables (allows you
+  to load lists and other complex objects from env vars).
 
 ## [0.2.0] - 2022-10-21
 ### Added

src/lib.rs

@@ -320,11 +320,14 @@ pub use crate::{
 /// - **`#[config(deserialize_with = path::to::function)]`**: like
 ///   [serde's `deserialize_with` attribute][serde-deser].
 ///
-/// [serde-deser]: https://serde.rs/field-attrs.html#deserialize_with
+/// - **`#[config(parse_env = path::to::function)]`**: function used to parse
+///     environment variables. Mostly useful if you need to parse lists or
+///     other complex objects from env vars. Function needs signature
+///     `fn(&str) -> Result<T, impl std::error::Error>` where `T` is the type of
+///     the field.. Can only be present if the `env` attribute is present. Also
+///     see [`env::parse`].
 ///
-/// - **`#[config(from_env = path::to::function, env = "KEY")]`**: like
-///   deserialize_with` attribute, but only for fields from an environment variable. 
-///   Can only be present if the `env` attribute is present
+/// [serde-deser]: https://serde.rs/field-attrs.html#deserialize_with
 ///
 /// ## Special types for leaf fields
 ///