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-rw-r--r--rand/rand-derive/src/lib.rs116
1 files changed, 0 insertions, 116 deletions
diff --git a/rand/rand-derive/src/lib.rs b/rand/rand-derive/src/lib.rs
deleted file mode 100644
index 80c803a..0000000
--- a/rand/rand-derive/src/lib.rs
+++ /dev/null
@@ -1,116 +0,0 @@
-//! Support for `#[derive(Rand)]`
-//!
-//! # Examples
-//!
-//! ```
-//! extern crate rand;
-//! #[macro_use]
-//! extern crate rand_derive;
-//!
-//! #[derive(Rand, Debug)]
-//! struct MyStruct {
-//! a: i32,
-//! b: u32,
-//! }
-//!
-//! fn main() {
-//! println!("{:?}", rand::random::<MyStruct>());
-//! }
-//! ```
-
-extern crate proc_macro;
-#[macro_use]
-extern crate quote;
-extern crate syn;
-
-use proc_macro::TokenStream;
-
-#[proc_macro_derive(Rand)]
-pub fn rand_derive(input: TokenStream) -> TokenStream {
- let s = input.to_string();
- let ast = syn::parse_derive_input(&s).unwrap();
- let gen = impl_rand_derive(&ast);
- gen.parse().unwrap()
-}
-
-fn impl_rand_derive(ast: &syn::MacroInput) -> quote::Tokens {
- let name = &ast.ident;
- let (impl_generics, ty_generics, where_clause) = ast.generics.split_for_impl();
-
- let rand = match ast.body {
- syn::Body::Struct(syn::VariantData::Struct(ref body)) => {
- let fields = body
- .iter()
- .filter_map(|field| field.ident.as_ref())
- .map(|ident| quote! { #ident: __rng.gen() })
- .collect::<Vec<_>>();
-
- quote! { #name { #(#fields,)* } }
- },
- syn::Body::Struct(syn::VariantData::Tuple(ref body)) => {
- let fields = (0..body.len())
- .map(|_| quote! { __rng.gen() })
- .collect::<Vec<_>>();
-
- quote! { #name (#(#fields),*) }
- },
- syn::Body::Struct(syn::VariantData::Unit) => {
- quote! { #name }
- },
- syn::Body::Enum(ref body) => {
- if body.is_empty() {
- panic!("`Rand` cannot be derived for enums with no variants");
- }
-
- let len = body.len();
- let mut arms = body
- .iter()
- .map(|variant| {
- let ident = &variant.ident;
- match variant.data {
- syn::VariantData::Struct(ref body) => {
- let fields = body
- .iter()
- .filter_map(|field| field.ident.as_ref())
- .map(|ident| quote! { #ident: __rng.gen() })
- .collect::<Vec<_>>();
- quote! { #name::#ident { #(#fields,)* } }
- },
- syn::VariantData::Tuple(ref body) => {
- let fields = (0..body.len())
- .map(|_| quote! { __rng.gen() })
- .collect::<Vec<_>>();
-
- quote! { #name::#ident (#(#fields),*) }
- },
- syn::VariantData::Unit => quote! { #name::#ident }
- }
- });
-
- match len {
- 1 => quote! { #(#arms)* },
- 2 => {
- let (a, b) = (arms.next(), arms.next());
- quote! { if __rng.gen() { #a } else { #b } }
- },
- _ => {
- let mut variants = arms
- .enumerate()
- .map(|(index, arm)| quote! { #index => #arm })
- .collect::<Vec<_>>();
- variants.push(quote! { _ => unreachable!() });
- quote! { match __rng.gen_range(0, #len) { #(#variants,)* } }
- },
- }
- }
- };
-
- quote! {
- impl #impl_generics ::rand::Rand for #name #ty_generics #where_clause {
- #[inline]
- fn rand<__R: ::rand::Rng>(__rng: &mut __R) -> Self {
- #rand
- }
- }
- }
-}