Refactor function parsing ♻

1 files changed, 5 insertions, 31 deletions

diff --git a/src/syntax/scope.rs b/src/syntax/scope.rs
index aac2b1b8..c17ff64d 100644
--- a/src/syntax/scope.rs
+++ b/src/syntax/scope.rs
@@ -3,8 +3,7 @@
 use std::collections::HashMap;
 use std::fmt::{self, Debug, Formatter};
 
-use super::parsing::{CallParser, ParseCall};
-use super::tree::DynamicNode;
+use super::parsing::CallParser;
 
 /// A map from identifiers to function parsers.
 pub struct Scope {
@@ -15,31 +14,16 @@ pub struct Scope {
 impl Scope {
     /// Create a new empty scope with a fallback parser that is invoked when no
     /// match is found.
-    pub fn new<F>() -> Self
-    where
-        F: ParseCall<Meta = ()> + DynamicNode + 'static
-    {
+    pub fn new(fallback: Box<CallParser>) -> Self {
         Self {
             parsers: HashMap::new(),
-            fallback: make_parser::<F>(()),
+            fallback,
         }
     }
 
     /// Associate the given function name with a dynamic node type.
-    pub fn add<F>(&mut self, name: &str)
-    where
-        F: ParseCall<Meta = ()> + DynamicNode + 'static
-    {
-        self.add_with_meta::<F>(name, ());
-    }
-
-    /// Add a dynamic node type with additional metadata that is passed to the
-    /// parser.
-    pub fn add_with_meta<F>(&mut self, name: &str, metadata: <F as ParseCall>::Meta)
-    where
-        F: ParseCall + DynamicNode + 'static
-    {
-        self.parsers.insert(name.to_string(), make_parser::<F>(metadata));
+    pub fn insert(&mut self, name: impl Into<String>, parser: Box<CallParser>) {
+        self.parsers.insert(name.into(), parser);
     }
 
     /// Return the parser with the given name if there is one.
@@ -58,13 +42,3 @@ impl Debug for Scope {
         f.debug_set().entries(self.parsers.keys()).finish()
     }
 }
-
-fn make_parser<F>(metadata: <F as ParseCall>::Meta) -> Box<CallParser>
-where
-    F: ParseCall + DynamicNode + 'static,
-{
-    Box::new(move |f, s| {
-        F::parse(f, s, metadata.clone())
-            .map(|tree| Box::new(tree) as Box<dyn DynamicNode>)
-    })
-}