Finally figured out how I want atoms to work

orchid-extension/src/lexer.rs

@@ -0,0 +1,34 @@
+use std::ops::RangeInclusive;
+
+use orchid_api::error::ProjResult;
+use orchid_api::tree::TokenTree;
+
+pub trait Lexer: Send + Sync + Sized + Default + 'static {
+  const CHAR_FILTER: &'static [RangeInclusive<char>];
+  fn lex<'a>(
+    tail: &'a str,
+    recur: impl FnMut(&'a str) -> ProjResult<(&'a str, TokenTree)>,
+  ) -> Option<ProjResult<(&'a str, TokenTree)>>;
+}
+
+pub trait DynLexer: Send + Sync + 'static {
+  fn char_filter(&self) -> &'static [RangeInclusive<char>];
+  fn lex<'a>(
+    &self,
+    tail: &'a str,
+    recur: &mut dyn FnMut(&'a str) -> ProjResult<(&'a str, TokenTree)>,
+  ) -> Option<ProjResult<(&'a str, TokenTree)>>;
+}
+
+impl<T: Lexer> DynLexer for T {
+  fn char_filter(&self) -> &'static [RangeInclusive<char>] { T::CHAR_FILTER }
+  fn lex<'a>(
+    &self,
+    tail: &'a str,
+    recur: &mut dyn FnMut(&'a str) -> ProjResult<(&'a str, TokenTree)>,
+  ) -> Option<ProjResult<(&'a str, TokenTree)>> {
+    T::lex(tail, recur)
+  }
+}
+
+pub type LexerObj = &'static dyn DynLexer;