error: mismatched function-like proc macro signature --> $DIR/signature-proc-macro.rs:10:25 | LL | pub fn bad_input(input: String) -> TokenStream { | ^^^^^^ found std::string::String, expected type `proc_macro::TokenStream` | = note: function-like proc macros must have a signature of `fn(TokenStream) -> TokenStream` error: mismatched function-like proc macro signature --> $DIR/signature-proc-macro.rs:16:42 | LL | pub fn bad_output(input: TokenStream) -> String { | ^^^^^^ found std::string::String, expected type `proc_macro::TokenStream` | = note: function-like proc macros must have a signature of `fn(TokenStream) -> TokenStream` error: mismatched function-like proc macro signature --> $DIR/signature-proc-macro.rs:22:41 | LL | pub fn bad_everything(input: String) -> String { | ^^^^^^ found std::string::String, expected type `proc_macro::TokenStream` | = note: function-like proc macros must have a signature of `fn(TokenStream) -> TokenStream` error: mismatched function-like proc macro signature --> $DIR/signature-proc-macro.rs:22:30 | LL | pub fn bad_everything(input: String) -> String { | ^^^^^^ found std::string::String, expected type `proc_macro::TokenStream` | = note: function-like proc macros must have a signature of `fn(TokenStream) -> TokenStream` error: mismatched function-like proc macro signature --> $DIR/signature-proc-macro.rs:29:33 | LL | pub fn too_many(a: TokenStream, b: TokenStream, c: String) -> TokenStream { | ^^^^^^^^^^^^^^^^^^^^^^^^^ found unexpected arguments error: aborting due to 5 previous errors