// force-host // no-prefer-dynamic #![feature(proc_macro_quote)] #![crate_type = "proc-macro"] extern crate proc_macro; use proc_macro::{TokenStream, TokenTree, Spacing, Literal, quote}; #[proc_macro] pub fn count_compound_ops(input: TokenStream) -> TokenStream { assert_eq!(count_compound_ops_helper(quote!(++ (&&) 4@a)), 3); let l = Literal::u32_suffixed(count_compound_ops_helper(input)); TokenTree::from(l).into() } fn count_compound_ops_helper(input: TokenStream) -> u32 { let mut count = 0; for token in input { match &token { TokenTree::Punct(tt) if tt.spacing() == Spacing::Alone => { count += 1; } TokenTree::Group(tt) => { count += count_compound_ops_helper(tt.stream()); } _ => {} } } count }