Synonym
Overview
The synonym library is a Rust crate designed to simplify the creation of newtypes. It provides a customizable #[derive(Synonym)] macro that automatically implements various traits based on the underlying type of your newtype. This saves you from the boilerplate code usually required when defining newtypes.
Usage
To use synonym, add it to your Cargo.toml:
[]
= "0.1.5"
Basic example
Import the Synonym trait into your Rust file:
use Synonym;
Then, define your newtype and annotate it with #[derive(Synonym)]:
;
Customization with Attributes
You can customize which traits are implemented or skipped using the #[synonym(skip(...))] and #[synonym(force(...))] attributes:
;
Supported skip and force values are listed in the Trait implementation table below.
Generated code
When you use #[derive(Synonym)], the library generates implementations for various traits. Here's a simplified example for a newtype MyInt(i32):
// ... and so on for other traits
Trait implementation table
Custom methods
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| .as_str() | String | v | v | v | v | |||
| .value() [2] | Value | v | v | v | v | v | v | v |
Conversion
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| AsRef | AsRef | v | v | v | v | v | v | v |
| Borrow | String | v | v | v | ||||
| From<&'a str> | String | v | v [4] | |||||
| From | String | v | ||||||
| Deref [3] | Deref | |||||||
| DerefMut [3] | DerefMut | |||||||
| From | From | v | v | v | v | v | v | v |
| FromStr | FromStr | v | v | v | v | v | v |
Fundamental traits
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| Clone | Clone | v | v | v | v | v | v | v |
| Copy | Copy | v | v | v | v | v | ||
| Debug | Debug | v | v | v | v | v | v | v |
| Default | Default | v | v | v | v | v | v | |
| Display [5] | Display | v | v | v | v | v | v | v |
| Hash | Hash | v | v | v | v | v | v |
Comparison
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| PartialOrd | PartialOrd | v | v | v | v | v | v | v |
| Ord | Ord | v | v | v | v | v | v | |
| PartialEq | PartialEq | v | v | v | v | v | v | v |
| Eq | Eq | v | v | v | v | v | v |
Serde [6]
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| Serialize | Serialize | v | v | v | v | v | v | |
| Deserialize | Deserialize | v | v | v | v | v | v |
Maths [7]
| skip/force | Integer [1] |
NonZero* |
Float |
String |
Box<str> |
&'static str |
char |
|
|---|---|---|---|---|---|---|---|---|
| Add=Self | Number | v | v | |||||
| AddAssign | Number | v | v | |||||
| Sub=Self | Number | v | v | |||||
| SubAssign | Number | v | v | |||||
| Mul=Self | Number | v | v | |||||
| MulAssign | Number | v | v | |||||
| Div=Self | Number | v | v | |||||
| DivAssign | Number | v | v |
[1] Integers are: u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize
[2] .value() returns Inner for Copy types and &Inner for non-Copy types
[3] Deref and DerefMut are never implemented unless they are forced with #[synonym(force(deref,deref_mut))]
[4] In constrast to other strings, FromStr for Box<str> synonyms uses Inner::From<&'str> instead of Inner::FromStr since there is no FromStr implementation for Box<str>
[5] Display implementation can be configured, see below
[6] Only provided when feature with_serde is enabled
[7] This is subject to change
Fine-tuning
Display
To specify how the Display trait should be implemented, you can use the #[synonym(display = "...")] attribute. Here are the available options:
Opaque: Formats the output as TypeName(Value).Transparent: Directly uses the inner type's Display implementation.UpperCase: Converts the inner value to uppercase before displaying.LowerCase: Converts the inner value to lowercase before displaying.OpaqueUpperCase: Formats the output as TypeName(VALUE) where VALUE is uppercase.OpaqueLowerCase: Formats the output as TypeName(value) where value is lowercase.Custom string: Allows for a custom format string
Examples
;
;
Serde Support
To enable Serde support for serialization and deserialization, you'll need to enable the with_serde feature flag in your Cargo.toml:
[]
= { = "0.1.5", = ["with_serde"] }
With this feature enabled, the Serialize and Deserialize traits will be automatically implemented for your type.
This documentation was generated with the assistance of ChatGPT-4 by OpenAI.
License
Licensed under of MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)
Contribution
All contributions and comments are more than welcome! Don't be afraid to open an issue or PR whenever you find a bug or have an idea to improve this crate.