getter 和 setter
Cargo.toml:
[package]
name = "gettersetter"
version = "0.1.0"
[lib]
proc-macro=true
[dependencies]
quote="^0.3.12"
syn="^0.11.4"
SRC / lib.rs:
#![crate_type = "proc-macro"]
extern crate proc_macro;
use proc_macro::TokenStream;
extern crate syn;
#[macro_use]
extern crate quote;
#[proc_macro_derive(GetSet)]
pub fn qqq(input: TokenStream) -> TokenStream {
let source = input.to_string();
let ast = syn::parse_derive_input(&source).unwrap();
let struct_name = &ast.ident;
if let syn::Body::Struct(s) = ast.body {
let field_names : Vec<_> = s.fields().iter().map(|ref x|
x.ident.clone().unwrap()).collect();
let field_getter_names = field_names.iter().map(|ref x|
syn::Ident::new(format!("get_{}", x).as_str()));
let field_setter_names = field_names.iter().map(|ref x|
syn::Ident::new(format!("set_{}", x).as_str()));
let field_types : Vec<_> = s.fields().iter().map(|ref x|
x.ty.clone()).collect();
let field_names2 = field_names.clone();
let field_names3 = field_names.clone();
let field_types2 = field_types.clone();
let quoted_code = quote!{
#[allow(dead_code)]
impl #struct_name {
#(
fn #field_getter_names(&self) -> &#field_types {
&self.#field_names2
}
fn #field_setter_names(&mut self, x : #field_types2) {
self.#field_names3 = x;
}
)*
}
};
return quoted_code.parse().unwrap();
}
// not a struct
"".parse().unwrap()
}
例項/ hello.rs:
#[macro_use]
extern crate gettersetter;
#[derive(GetSet)]
struct Qqq {
x : i32,
y : String,
}
fn main(){
let mut a = Qqq { x: 3, y: "zzaaqq".to_string() };
println!("{}", a.get_x());
a.set_y("123213".to_string());
println!("{}", a.get_y());
}
另請參見: https : //github.com/emk/accessors