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-rw-r--r--syn-mid/examples/const_fn/lib.rs31
1 files changed, 0 insertions, 31 deletions
diff --git a/syn-mid/examples/const_fn/lib.rs b/syn-mid/examples/const_fn/lib.rs
deleted file mode 100644
index 29255f2..0000000
--- a/syn-mid/examples/const_fn/lib.rs
+++ /dev/null
@@ -1,31 +0,0 @@
-#![warn(rust_2018_idioms)]
-
-extern crate proc_macro;
-
-use proc_macro::TokenStream;
-use proc_macro2::TokenStream as TokenStream2;
-use quote::quote;
-use syn_mid::ItemFn;
-
-/// An attribute for easy generation of a const function with conditional compilations.
-#[proc_macro_attribute]
-pub fn const_fn(args: TokenStream, function: TokenStream) -> TokenStream {
- assert!(!args.is_empty(), "requires an argument");
-
- let mut function = syn::parse_macro_input!(function as ItemFn);
- let mut const_function = function.clone();
-
- if function.constness.is_some() {
- function.constness = None;
- } else {
- const_function.constness = Some(Default::default());
- }
-
- let args = TokenStream2::from(args);
- TokenStream::from(quote! {
- #[cfg(not(#args))]
- #function
- #[cfg(#args)]
- #const_function
- })
-}