4 files changed, 35 insertions, 64 deletions

diff --git a/src/parser/grammar/attributes.rs b/src/parser/grammar/attributes.rs
index 92dfb99ef..7f1c0401a 100644
--- a/src/parser/grammar/attributes.rs
+++ b/src/parser/grammar/attributes.rs
@@ -1,7 +1,7 @@
 use super::*;
 
 pub(super) fn inner_attributes(p: &mut Parser) {
-    while p.at([POUND, EXCL]) {
+    while p.current() == POUND && p.nth(1) == EXCL {
         attribute(p, true)
     }
 }
diff --git a/src/parser/grammar/mod.rs b/src/parser/grammar/mod.rs
index 5266354c1..f5b63aaab 100644
--- a/src/parser/grammar/mod.rs
+++ b/src/parser/grammar/mod.rs
@@ -110,65 +110,3 @@ fn error_block(p: &mut Parser, message: &str) {
     }
     err.complete(p, ERROR);
 }
-
-impl<'p> Parser<'p> {
-    fn at<L: Lookahead>(&self, l: L) -> bool {
-        l.is_ahead(self)
-    }
-
-    fn err_and_bump(&mut self, message: &str) {
-        let err = self.start();
-        self.error(message);
-        self.bump();
-        err.complete(self, ERROR);
-    }
-
-    fn expect(&mut self, kind: SyntaxKind) -> bool {
-        if self.at(kind) {
-            self.bump();
-            true
-        } else {
-            self.error(format!("expected {:?}", kind));
-            false
-        }
-    }
-
-    fn eat(&mut self, kind: SyntaxKind) -> bool {
-        self.current() == kind && {
-            self.bump();
-            true
-        }
-    }
-}
-
-trait Lookahead: Copy {
-    fn is_ahead(self, p: &Parser) -> bool;
-}
-
-impl Lookahead for SyntaxKind {
-    fn is_ahead(self, p: &Parser) -> bool {
-        p.current() == self
-    }
-}
-
-impl Lookahead for [SyntaxKind; 2] {
-    fn is_ahead(self, p: &Parser) -> bool {
-        p.current() == self[0] && p.nth(1) == self[1]
-    }
-}
-
-impl Lookahead for [SyntaxKind; 3] {
-    fn is_ahead(self, p: &Parser) -> bool {
-        p.current() == self[0] && p.nth(1) == self[1] && p.nth(2) == self[2]
-    }
-}
-
-#[derive(Clone, Copy)]
-struct AnyOf<'a>(&'a [SyntaxKind]);
-
-impl<'a> Lookahead for AnyOf<'a> {
-    fn is_ahead(self, p: &Parser) -> bool {
-        let curr = p.current();
-        self.0.iter().any(|&k| k == curr)
-    }
-}
diff --git a/src/parser/grammar/paths.rs b/src/parser/grammar/paths.rs
index 6ed315c3d..d3eb20ea1 100644
--- a/src/parser/grammar/paths.rs
+++ b/src/parser/grammar/paths.rs
@@ -1,7 +1,10 @@
 use super::*;
 
 pub(super) fn is_path_start(p: &Parser) -> bool {
-    AnyOf(&[IDENT, SELF_KW, SUPER_KW, COLONCOLON]).is_ahead(p)
+    match p.current() {
+        IDENT | SELF_KW | SUPER_KW | COLONCOLON => true,
+        _ => false,
+    }
 }
 
 pub(super) fn use_path(p: &mut Parser) {
diff --git a/src/parser/mod.rs b/src/parser/mod.rs
index 49a69900f..c23ed3349 100644
--- a/src/parser/mod.rs
+++ b/src/parser/mod.rs
@@ -26,3 +26,33 @@ fn is_insignificant(kind: SyntaxKind) -> bool {
         _ => false,
     }
 }
+
+impl<'p> parser::Parser<'p> {
+    fn at(&self, kind: SyntaxKind) -> bool {
+        self.current() == kind
+    }
+
+    fn err_and_bump(&mut self, message: &str) {
+        let err = self.start();
+        self.error(message);
+        self.bump();
+        err.complete(self, ERROR);
+    }
+
+    fn expect(&mut self, kind: SyntaxKind) -> bool {
+        if self.at(kind) {
+            self.bump();
+            true
+        } else {
+            self.error(format!("expected {:?}", kind));
+            false
+        }
+    }
+
+    fn eat(&mut self, kind: SyntaxKind) -> bool {
+        self.at(kind) && {
+            self.bump();
+            true
+        }
+    }
+}