Rust-Property

Generate several common methods for structs automatically.

Usage

Apply the derive proc-macro #[derive(Property)] to structs, and use #[property(..)] to configure it.

There are three levels of properties:

• Set crate properties can change the default settings for all containers (structs) in the whole crate.

  Limited by the procedural macros, here we have to use a tricky way to set the crate properties:

  #[property_default(get(..), set(..), ..)]
  struct PropertyCrateConf; // This struct is only used for introducing the attribute macro, and it will be removed in the macro.

• Set container properties can change the default properties for all fields in the container.

• Change the settings of a single field via setting field properties.

If no properties is set, the default properties will be applied:

#[property(
    get(crate, prefix = "", suffix = "", type="auto"),
    set(crate, prefix = "set_", type = "ref"),
    mut(crate, prefix = "mut_"),
    clr(crate, prefix = "clear_", scope = "option")
    ord(asc)
)]

There are six kinds of configurable properties: skip, get, set, mut, clr and ord.

• If the skip property is set, no methods will be generated.

• The visibility of a method can be set via #[property(get(visibility-type))]

  There are four kinds of the visibility types: disable, public, crate (default for all methods), and private.

• The method name can be set in two ways:

  1. Assign a complete name via #[property(get(name = "method-name"))].

  2. Set prefix and / or suffix via #[property(set(prefix = "set_"), mut(suffix = "mut_"))].

  The default setting for all fields is: #[property(get(prefix = "", suffix = ""), set(prefix = "set_"), mut(prefix = "mut_"))].

• The return type of get method can be set via #[property(get(type = "return-type"))].

  There are four kinds of the return types: auto (default), ref, clone and copy.

• The input type and return type of set method can be set via #[property(set(type = "set-type"))].

  There are four kinds of the input types: ref (default), own, none and replace:

  • ref: input is a mutable reference and return is the mutable reference too.

  • own: input is a owned object and return is the owned object too.

  • none: input is a mutable reference and no return.

  • replace: input is a mutable reference and return the old value.

• There is an extra property for set method:

  • full_option: if the value is Option<T>, then the default argument is T without this property.

• The clr method will set a field to its default value. It has a scope property:

  • auto: will generate clr method for some preset types, such as Vec, Option, and so on.

  • option: (default) will generate clr method for Option only.

  • all: will generate clr method for all types.

• If there are more than one filed have the ord property, the PartialEq and PartialOrd will be implemented automatically.

  • A serial number is required for the ord field property, it's an unsigned number with a _ prefix.

    The serial numbers could be noncontinuous, but any two number of these could not be equal.

    No serial number is allowed if the ord property is a container property.

  • There are two kind of sort types: asc and desc.

    The default is ascending (asc), it can be changed to descending if the desc was set.

In Action

Original Code

#![no_std]

#[cfg(not(feature = "std"))]
extern crate alloc;

#[cfg(feature = "std")]
extern crate std as alloc;

use alloc::{string::String, vec::Vec};

use property::{property_default, Property};

#[property_default(get(public), ord(desc), clr(scope = "option"))]
struct PropertyCrateConf;

#[derive(Copy, Clone)]
pub enum Species {
    Dog,
    Cat,
    Bird,
    Other,
}

#[derive(Property)]
#[property(set(private), mut(disable))]
pub struct Pet {
    #[property(get(name = "identification"), set(disable), ord(asc, _2))]
    id: [u8; 32],
    name: String,
    #[property(set(crate, type = "own"), ord(_0))]
    age: u32,
    #[property(get(type = "copy"))]
    species: Species,
    #[property(get(prefix = "is_"), ord(_1))]
    died: bool,
    #[property(get(type = "clone"), set(type = "none"))]
    owner: String,
    #[property(clr(scope = "auto"))]
    family_members: Vec<String>,
    #[property(get(type = "ref"), mut(crate))]
    info: String,
    #[property(get(disable), set(type = "replace"))]
    pub tag: Vec<String>,
    #[property(mut(public, suffix = "_mut"))]
    note: Option<String>,
    #[property(set(type = "replace", full_option))]
    price: Option<u32>,
    #[property(skip)]
    pub reserved: String,
}

Generated Code

impl Pet {
    #[inline]
    pub fn identification(&self) -> &[u8] {
        &self.id[..]
    }
    #[inline]
    pub fn name(&self) -> &str {
        &self.name[..]
    }
    #[inline]
    fn set_name<T: Into<String>>(&mut self, val: T) -> &mut Self {
        self.name = val.into();
        self
    }
    #[inline]
    pub fn age(&self) -> u32 {
        self.age
    }
    #[inline]
    pub(crate) fn set_age<T: Into<u32>>(mut self, val: T) -> Self {
        self.age = val.into();
        self
    }
    #[inline]
    pub fn species(&self) -> Species {
        self.species
    }
    #[inline]
    fn set_species<T: Into<Species>>(&mut self, val: T) -> &mut Self {
        self.species = val.into();
        self
    }
    #[inline]
    pub fn is_died(&self) -> bool {
        self.died
    }
    #[inline]
    fn set_died<T: Into<bool>>(&mut self, val: T) -> &mut Self {
        self.died = val.into();
        self
    }
    #[inline]
    pub fn owner(&self) -> String {
        self.owner.clone()
    }
    #[inline]
    fn set_owner<T: Into<String>>(&mut self, val: T) {
        self.owner = val.into();
    }
    #[inline]
    pub fn family_members(&self) -> &[String] {
        &self.family_members[..]
    }
    #[inline]
    fn set_family_members<T: Into<String>>(
        &mut self,
        val: impl IntoIterator<Item = T>,
    ) -> &mut Self {
        self.family_members = val.into_iter().map(Into::into).collect();
        self
    }
    #[inline]
    pub(crate) fn clear_family_members(&mut self) {
        self.family_members.clear();
    }
    #[inline]
    pub fn info(&self) -> &String {
        &self.info
    }
    #[inline]
    fn set_info<T: Into<String>>(&mut self, val: T) -> &mut Self {
        self.info = val.into();
        self
    }
    #[inline]
    pub(crate) fn mut_info(&mut self) -> &mut String {
        &mut self.info
    }
    #[inline]
    fn set_tag<T: Into<String>>(&mut self, val: impl IntoIterator<Item = T>) -> Vec<String> {
        ::core::mem::replace(&mut self.tag, val.into_iter().map(Into::into).collect())
    }
    #[inline]
    pub fn note(&self) -> Option<&String> {
        self.note.as_ref()
    }
    #[inline]
    fn set_note<T: Into<String>>(&mut self, val: T) -> &mut Self {
        self.note = Some(val.into());
        self
    }
    #[inline]
    pub fn note_mut(&mut self) -> &mut Option<String> {
        &mut self.note
    }
    #[inline]
    pub(crate) fn clear_note(&mut self) {
        self.note = None;
    }
    #[inline]
    pub fn price(&self) -> Option<u32> {
        self.price
    }
    #[inline]
    fn set_price<T: Into<Option<u32>>>(&mut self, val: T) -> Option<u32> {
        ::core::mem::replace(&mut self.price, val.into())
    }
    #[inline]
    pub(crate) fn clear_price(&mut self) {
        self.price = None;
    }
}
impl PartialEq for Pet {
    fn eq(&self, other: &Self) -> bool {
        self.age == other.age && self.died == other.died && self.id == other.id
    }
}
impl PartialOrd for Pet {
    fn partial_cmp(&self, other: &Self) -> Option<::core::cmp::Ordering> {
        let result = other.age.partial_cmp(&self.age);
        if result != Some(::core::cmp::Ordering::Equal) {
            return result;
        }
        let result = other.died.partial_cmp(&self.died);
        if result != Some(::core::cmp::Ordering::Equal) {
            return result;
        }
        let result = self.id.partial_cmp(&other.id);
        if result != Some(::core::cmp::Ordering::Equal) {
            return result;
        }
        Some(::core::cmp::Ordering::Equal)
    }
}

Enjoy it!

Minimum Supported Rust Version

Rust 1.31.0.

License

Licensed under either of Apache License, Version 2.0 or MIT License, at your option.