diff --git a/index.html b/index.html
index c54128c..40b85af 100644
--- a/index.html
+++ b/index.html
@@ -40,15 +40,18 @@ <h1>
 # Multiple definition
 true = not false
 
-# Invalid names
-%value = ()
-
 # Invalid whitespace (tabs)
 whitespace	=	()
 
-# Bare term
+# Bare lambda
 (\ f x . f (x x))
 
+# Bare term
+const f x
+
+# Symbols
+< a b c >  => < a a a >
+
 # Unbound
 some-func = \ local . true non-existent local
 
@@ -58,9 +61,18 @@ <h1>
 # Debug mode on
 #debug
 
-# Bare term - Debug
+# Invalid names - Debug
+%value = ()
+
+# Bare lambda - Debug
 (\ f x . f (x x))
 
+# Bare term - Debug
+const f x
+
+# Symbols - Debug
+< a b c >  => < a a a >
+
 # Unbound - Debug
 some-func = \ local . true non-existent local
 
@@ -104,7 +116,7 @@ <h1>
 chunk = \ a b xs . row-s a (colS b xs)
 append = \ as bs . null as bs (cons (head as) (append (tail as) bs))
 concat = foldr append nil
-eq = \ a b . is-z a (is-z b) (is-z b false (eq (pred a) (pred b)))
+eq? = \ a b . is-z a (is-z b) (is-z b false (eq? (pred a) (pred b)))
 all = foldr (\ a b . a b false) true
 allf = \ f xs . all (map f xs)
 </textarea>
diff --git a/lambdacalc.js b/lambdacalc.js
index 09b7f05..47c00fe 100644
--- a/lambdacalc.js
+++ b/lambdacalc.js
@@ -14,23 +14,24 @@ CodeMirror.defineMode("lambdacalc", function(_config, modeConfig) {
   const EMPTY = "text";
   const UNDEF = "error";
   const REDEF = "variable-3";
+  const SUPPRESS = "text";
   const FAIL = "error";
 
-  const defName = /[a-zA-Z][a-zA-Z0-9_\-']*/
+  const defName = /[a-zA-Z][-'\w]*\??/
   const assign = /=/
   const brack = /\(|\)/
-  const lamArg = /[a-zA-Z_][a-zA-Z0-9_\-']*|\./
-  const numconst = /\d+/
+  const lamArg = /[_a-zA-Z][-'\w]*\??|\./
+  const numconst = /-?\d+/
 
   function expectDefOrTerm(stream, state) {
-    return expectDef(stream, state)
-      || (state.debug ? null : expectTerm(stream, state));
+    if (stream.match(/.*=/, false)) return expectDef(stream, state);
+    else return expectTerm(stream, state);
   }
 
   function expectDef(stream, state) {
     const name = (stream.match(defName)||[])[0];
     state.f = expectAssign;
-    if (!name || !(/[=\s]/.test(stream.peek()) || stream.eol())) return null;
+    if (!name || !(stream.match(/\s*=/, false))) return null;
     const res = [];
     if (state.defined.includes(name)) res.push(REDEF);
     state.defined.push(name);
@@ -63,6 +64,7 @@ CodeMirror.defineMode("lambdacalc", function(_config, modeConfig) {
       state.bound.push([]);
     }
     else {
+      if (!(state.depth.length && state.bound.length)) return FAIL;
       state.depth.pop();
       state.bound.pop();
     }
@@ -81,7 +83,7 @@ CodeMirror.defineMode("lambdacalc", function(_config, modeConfig) {
     if (!res) return null;
     if (state.bound.some(v=>v.includes(res))) return BOUND;
     if (state.defined.includes(res)) return PREDEF;
-    return state.debug ? UNDEF : "text";
+    return UNDEF;
   }
 
   function number(stream, state) {
@@ -102,13 +104,13 @@ CodeMirror.defineMode("lambdacalc", function(_config, modeConfig) {
   }
 
   function onFail(stream, state) {
-    stream.match(/[^\s]*/);
-    return FAIL
+    stream.match(/[^\s#]*/);
+    return FAIL ;
   }
 
   return {
     startState: function ()  { return {
-      f: expectDefOrTerm,
+      f: expectDef,
       depth: [],
       defined: [],
       bound: [[]],
@@ -136,13 +138,15 @@ CodeMirror.defineMode("lambdacalc", function(_config, modeConfig) {
       }
       if (stream.sol() && state.depth.length === 0) {
         state.bound = [[]];
-        state.f = expectDefOrTerm;
+        state.f = expectDef;
       }
-      return state.f(stream, state) || onFail(stream, state);
+      const res = state.f(stream, state)
+        || (state.debug ? null : expectDefOrTerm(stream, state))
+        || onFail(stream, state);
+      return !state.debug && res == FAIL ? SUPPRESS : res ;
     },
 
     indent: function(state, textAfter) {
-      console.log(state.depth);
       if (!state.depth.length) return 0;
       return state.depth[state.depth.length-1] + 2;
     },
diff --git a/package-lock.json b/package-lock.json
index e31df3d..5f0a862 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@codewars/codemirror-lambda-calculus",
-  "version": "0.2.0",
+  "version": "0.3.4",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "@codewars/codemirror-lambda-calculus",
-      "version": "0.2.0",
+      "version": "0.3.4",
       "license": "MIT",
       "devDependencies": {
         "postcss-nesting": "^10.1.2",
diff --git a/package.json b/package.json
index d60b3d9..b6463e5 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@codewars/codemirror-lambda-calculus",
-  "version": "0.2.0",
+  "version": "0.3.4",
   "type": "module",
   "description": "Lambda Calculus mode for CodeMirror",
   "main": "lambdacalc.js",