Remove error checks for mixing up PEG rule and Rust value arguments

When a rule with PEG rule closure arguments is recursive, it can be useful to pass down the rule argument as a value, since re-capturing it results in a type-length limit error from rustc. (#226) Rustc's type error if you do pass the wrong type isn't as good as the custom one, but isn't too bad.
kevinmehall · Mar 14, 2021 · 1071e80 · 1071e80
1 parent 2dacb48
commit 1071e80
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Showing 3 changed files with 2 additions and 42 deletions.
diff --git a/peg-macros/translate.rs b/peg-macros/translate.rs
@@ -471,31 +471,6 @@ fn compile_expr(context: &Context, e: &SpannedExpr, result_used: bool) -> TokenS
                 );
             }
 
-            for (param, arg) in rule_def.params.iter().zip(rule_args.iter()) {
-                match (&param.ty, &arg) {
-                    (RuleParamTy::Rust(..), RuleArg::Peg(..)) => {
-                        return report_error_expr(
-                            rule_name.span(),
-                            format!(
-                                "parameter `{}` expects a value, but a PEG expression was passed",
-                                param.name
-                            ),
-                        );
-                    }
-                    (RuleParamTy::Rule(..), RuleArg::Rust(..)) => {
-                        return report_error_expr(
-                            rule_name.span(),
-                            format!(
-                                "parameter `{}` expects a PEG expression, but a value was passed",
-                                param.name
-                            ),
-                        );
-                    }
-                    (RuleParamTy::Rule(..), RuleArg::Peg(..)) => (),
-                    (RuleParamTy::Rust(..), RuleArg::Rust(..)) => (),
-                }
-            }
-
             let func = format_ident!("__parse_{}", rule_name, span = rule_name.span());
             let extra_args_call = &context.extra_args_call;
 

diff --git a/tests/compile-fail/rule_args_errors.rs b/tests/compile-fail/rule_args_errors.rs
@@ -7,9 +7,6 @@ peg::parser!(grammar foo() for str {
     rule too_few() = foo(1) //~ ERROR
     rule too_many() = foo(1, <[_]>, 2)  //~ ERROR
 
-    rule wrong_type1() = foo(<[_]>, 1) //~ ERROR
-    rule wrong_type2() = foo(1, 1) //~ ERROR
-
     pub rule pub_rule_arg(x: rule<()>) = "foo" //~ ERROR
 });
 

diff --git a/tests/compile-fail/rule_args_errors.stderr b/tests/compile-fail/rule_args_errors.stderr
@@ -10,20 +10,8 @@ error: this rule takes 2 parameters but 3 parameters were supplied
 8 |     rule too_many() = foo(1, <[_]>, 2)  //~ ERROR
   |                       ^^^
 
-error: parameter `x` expects a value, but a PEG expression was passed
-  --> $DIR/rule_args_errors.rs:10:26
-   |
-10 |     rule wrong_type1() = foo(<[_]>, 1) //~ ERROR
-   |                          ^^^
-
-error: parameter `y` expects a PEG expression, but a value was passed
-  --> $DIR/rule_args_errors.rs:11:26
-   |
-11 |     rule wrong_type2() = foo(1, 1) //~ ERROR
-   |                          ^^^
-
 error: parameters on `pub rule` must be Rust types
-  --> $DIR/rule_args_errors.rs:13:27
+  --> $DIR/rule_args_errors.rs:10:27
    |
-13 |     pub rule pub_rule_arg(x: rule<()>) = "foo" //~ ERROR
+10 |     pub rule pub_rule_arg(x: rule<()>) = "foo" //~ ERROR
    |                           ^