diff --git a/baselines/reference/es6.grammar.emu.html b/baselines/reference/es6.grammar.emu.html
index 1a54490..5659b61 100644
--- a/baselines/reference/es6.grammar.emu.html
+++ b/baselines/reference/es6.grammar.emu.html
@@ -352,9 +352,9 @@
 </emu-production>
 <emu-production name="EscapeSequence" type="lexical">
     <emu-rhs a="e9e86f07"><emu-nt>CharacterEscapeSequence</emu-nt></emu-rhs>
-    <emu-rhs a="3651e0da">
+    <emu-rhs a="6964a19d">
         <emu-t>0</emu-t>
-        <emu-gann>lookahead ≠ <emu-nt>DecimalDigit</emu-nt></emu-gann>
+        <emu-gann>lookahead ∉ <emu-nt>DecimalDigit</emu-nt></emu-gann>
     </emu-rhs>
     <emu-rhs a="a8071b85"><emu-nt>HexEscapeSequence</emu-nt></emu-rhs>
     <emu-rhs a="44bd6f55"><emu-nt>UnicodeEscapeSequence</emu-nt></emu-rhs>
diff --git a/baselines/reference/es6.grammar.html b/baselines/reference/es6.grammar.html
index 68773fc..3d0002b 100644
--- a/baselines/reference/es6.grammar.html
+++ b/baselines/reference/es6.grammar.html
@@ -632,7 +632,7 @@
                 <a name="e9e86f07"></a><span class="rhs"><span class="nonterminal"><a href="#CharacterEscapeSequence">CharacterEscapeSequence</a></span></span>
             </div>
             <div class="rhs-list-item">
-                <a name="3651e0da"></a><span class="rhs"><span class="terminal">0</span> <span class="assertion">[<span class="keyword">lookahead</span> ≠ <span class="nonterminal"><a href="#DecimalDigit">DecimalDigit</a></span>]</span></span>
+                <a name="6964a19d"></a><span class="rhs"><span class="terminal">0</span> <span class="assertion">[<span class="keyword">lookahead</span> ∉ <span class="nonterminal"><a href="#DecimalDigit">DecimalDigit</a></span>]</span></span>
             </div>
             <div class="rhs-list-item">
                 <a name="a8071b85"></a><span class="rhs"><span class="nonterminal"><a href="#HexEscapeSequence">HexEscapeSequence</a></span></span>
diff --git a/baselines/reference/es6.grammar.md b/baselines/reference/es6.grammar.md
index 6c2bb77..c83cff6 100644
--- a/baselines/reference/es6.grammar.md
+++ b/baselines/reference/es6.grammar.md
@@ -251,7 +251,7 @@
   
 &emsp;&emsp;<a name="EscapeSequence"></a>*EscapeSequence* **::**  
 &emsp;&emsp;&emsp;<a name="EscapeSequence-e9e86f07"></a>*[CharacterEscapeSequence](#CharacterEscapeSequence)*  
-&emsp;&emsp;&emsp;<a name="EscapeSequence-3651e0da"></a>`` 0 ``&emsp;[lookahead ≠ *[DecimalDigit](#DecimalDigit)*]  
+&emsp;&emsp;&emsp;<a name="EscapeSequence-6964a19d"></a>`` 0 ``&emsp;[lookahead ∉ *[DecimalDigit](#DecimalDigit)*]  
 &emsp;&emsp;&emsp;<a name="EscapeSequence-a8071b85"></a>*[HexEscapeSequence](#HexEscapeSequence)*  
 &emsp;&emsp;&emsp;<a name="EscapeSequence-44bd6f55"></a>*[UnicodeEscapeSequence](#UnicodeEscapeSequence)*  
   
diff --git a/baselines/reference/es6.grammar.nodes b/baselines/reference/es6.grammar.nodes
index 59322a8..5d0ebd0 100644
--- a/baselines/reference/es6.grammar.nodes
+++ b/baselines/reference/es6.grammar.nodes
@@ -1055,7 +1055,7 @@
             (265,6)SyntaxKind[LookaheadAssertion]
               (265,6)SyntaxKind[OpenBracketToken]
               (265,7)SyntaxKind[LookaheadKeyword]
-              (265,17)SyntaxKind[ExclamationEqualsToken]
+              (265,17)SyntaxKind[LessThanExclamationToken]
               (265,20)SyntaxKind[SymbolSpan]
                 (265,20)SyntaxKind[Nonterminal]
                   (265,20)SyntaxKind[Identifier](text = "DecimalDigit")
diff --git a/baselines/reference/es6.grammar.tokens b/baselines/reference/es6.grammar.tokens
index 23ba79a..097ea05 100644
--- a/baselines/reference/es6.grammar.tokens
+++ b/baselines/reference/es6.grammar.tokens
@@ -873,7 +873,7 @@ SyntaxKind[LineTerminatorToken](265,1): «line terminator»
 SyntaxKind[Terminal](265,2): `0`
 SyntaxKind[OpenBracketToken](265,6): [
 SyntaxKind[LookaheadKeyword](265,7): lookahead
-SyntaxKind[ExclamationEqualsToken](265,17): !=
+SyntaxKind[LessThanExclamationToken](265,17): <!
 SyntaxKind[Identifier](265,20): DecimalDigit
 SyntaxKind[CloseBracketToken](265,32): ]
 SyntaxKind[LineTerminatorToken](266,1): «line terminator»
diff --git a/baselines/reference/test.grammar.emu.html b/baselines/reference/test.grammar.emu.html
index 41c7365..9505a2b 100644
--- a/baselines/reference/test.grammar.emu.html
+++ b/baselines/reference/test.grammar.emu.html
@@ -41,4 +41,7 @@
 <emu-production name="Z">
     <del><emu-rhs a="6dcd4ce2"><emu-nt>A</emu-nt></emu-rhs></del>
     <ins><emu-rhs a="ae4f281d"><emu-nt>B</emu-nt></emu-rhs></ins>
+</emu-production>
+<emu-production name="LookaheadRestriction">
+    <emu-rhs a="5c1008f6"><emu-gann>lookahead ∉ <emu-nt>A</emu-nt></emu-gann></emu-rhs>
 </emu-production>
\ No newline at end of file
diff --git a/baselines/reference/test.grammar.html b/baselines/reference/test.grammar.html
index 4cf120c..9d461aa 100644
--- a/baselines/reference/test.grammar.html
+++ b/baselines/reference/test.grammar.html
@@ -64,4 +64,12 @@
             </div>
         </div>
     </div>
+    <a name="LookaheadRestriction"></a><div class="production">
+        <span class="nonterminal">LookaheadRestriction</span><span class="punctuation"> :</span>
+        <div class="rhs-list">
+            <div class="rhs-list-item">
+                <a name="5c1008f6"></a><span class="rhs"><span class="assertion">[<span class="keyword">lookahead</span> ∉ <span class="nonterminal"><a href="#A">A</a></span>]</span></span>
+            </div>
+        </div>
+    </div>
 </div>
\ No newline at end of file
diff --git a/baselines/reference/test.grammar.md b/baselines/reference/test.grammar.md
index 5249ae2..0545221 100644
--- a/baselines/reference/test.grammar.md
+++ b/baselines/reference/test.grammar.md
@@ -24,4 +24,7 @@
 &emsp;&emsp;<a name="Z"></a>*Z* **:**  
 &emsp;&emsp;&emsp;<del><a name="Z-6dcd4ce2"></a>*[A](#A)*</del>  
 &emsp;&emsp;&emsp;<ins><a name="Z-ae4f281d"></a>*[B](#B)*</ins>  
+  
+&emsp;&emsp;<a name="LookaheadRestriction"></a>*LookaheadRestriction* **:**  
+&emsp;&emsp;&emsp;<a name="LookaheadRestriction-5c1008f6"></a>[lookahead ∉ *[A](#A)*]  
   
\ No newline at end of file
diff --git a/baselines/reference/test.grammar.nodes b/baselines/reference/test.grammar.nodes
index 61207a7..14256ad 100644
--- a/baselines/reference/test.grammar.nodes
+++ b/baselines/reference/test.grammar.nodes
@@ -174,3 +174,18 @@
           (22,10)SyntaxKind[Nonterminal]
             (22,10)SyntaxKind[Identifier](text = "B")
       (23,1)SyntaxKind[DedentToken]
+  (24,1)SyntaxKind[Production]
+    (24,1)SyntaxKind[Identifier](text = "LookaheadRestriction")
+    (25,1)SyntaxKind[RightHandSideList]
+      (25,1)SyntaxKind[IndentToken]
+      (25,5)SyntaxKind[RightHandSide]
+        (25,5)SyntaxKind[SymbolSpan]
+          (25,5)SyntaxKind[LookaheadAssertion]
+            (25,5)SyntaxKind[OpenBracketToken]
+            (25,6)SyntaxKind[LookaheadKeyword]
+            (25,16)SyntaxKind[LessThanExclamationToken]
+            (25,19)SyntaxKind[SymbolSpan]
+              (25,19)SyntaxKind[Nonterminal]
+                (25,19)SyntaxKind[Identifier](text = "A")
+            (25,20)SyntaxKind[CloseBracketToken]
+      (25,21)SyntaxKind[DedentToken]
diff --git a/baselines/reference/test.grammar.tokens b/baselines/reference/test.grammar.tokens
index 026c505..0d3b949 100644
--- a/baselines/reference/test.grammar.tokens
+++ b/baselines/reference/test.grammar.tokens
@@ -118,4 +118,15 @@ SyntaxKind[LineTerminatorToken](22,1): «line terminator»
 SyntaxKind[Identifier](22,10): B
 SyntaxKind[LineTerminatorToken](23,1): «line terminator»
 SyntaxKind[DedentToken](23,1): «dedent»
-SyntaxKind[EndOfFileToken](23,1): «EndOfFileToken»
+SyntaxKind[LineTerminatorToken](24,1): «line terminator»
+SyntaxKind[Identifier](24,1): LookaheadRestriction
+SyntaxKind[ColonToken](24,21): :
+SyntaxKind[LineTerminatorToken](25,1): «line terminator»
+SyntaxKind[IndentToken](25,1): «indent»
+SyntaxKind[OpenBracketToken](25,5): [
+SyntaxKind[LookaheadKeyword](25,6): lookahead
+SyntaxKind[LessThanExclamationToken](25,16): <!
+SyntaxKind[Identifier](25,19): A
+SyntaxKind[CloseBracketToken](25,20): ]
+SyntaxKind[DedentToken](25,21): «dedent»
+SyntaxKind[EndOfFileToken](25,21): «EndOfFileToken»
diff --git a/grammars/es2015.grammar b/grammars/es2015.grammar
index 9da0784..fce46e9 100644
--- a/grammars/es2015.grammar
+++ b/grammars/es2015.grammar
@@ -262,7 +262,7 @@ LineContinuation ::
 
 EscapeSequence ::
 	CharacterEscapeSequence
-	`0` [lookahead != DecimalDigit]
+	`0` [lookahead <! DecimalDigit]
 	HexEscapeSequence
 	UnicodeEscapeSequence
 
diff --git a/package.json b/package.json
index 3aeda84..90c779a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "grammarkdown",
-  "version": "1.0.7",
+  "version": "1.0.8",
   "description": "Markdown-like DSL for defining syntactic grammars for programming languages.",
   "license": "Apache-2.0",
   "keywords": [
diff --git a/spec/es6.grammar b/spec/es6.grammar
index 9da0784..fce46e9 100644
--- a/spec/es6.grammar
+++ b/spec/es6.grammar
@@ -262,7 +262,7 @@ LineContinuation ::
 
 EscapeSequence ::
 	CharacterEscapeSequence
-	`0` [lookahead != DecimalDigit]
+	`0` [lookahead <! DecimalDigit]
 	HexEscapeSequence
 	UnicodeEscapeSequence
 
diff --git a/spec/test.grammar b/spec/test.grammar
index ca9bf28..4fbdf75 100644
--- a/spec/test.grammar
+++ b/spec/test.grammar
@@ -20,3 +20,6 @@ F[A] :
 Z :
     <del>A</del>
     <ins>B</ins>
+
+LookaheadRestriction:
+    [lookahead <! A]
\ No newline at end of file
diff --git a/src/lib/checker.ts b/src/lib/checker.ts
index 9bd1a98..eecb84b 100644
--- a/src/lib/checker.ts
+++ b/src/lib/checker.ts
@@ -484,7 +484,7 @@ export class Checker {
             return this.reportGrammarError(node.symbol.pos, Diagnostics._0_expected, tokenToString(SyntaxKind.LineTerminatorToken));
         }
 
-        if (node.next && node.next.kind === SyntaxKind.Prose) {
+        if (node.next && node.next.symbol.kind === SyntaxKind.Prose) {
             return this.reportGrammarError(node.next.pos, Diagnostics._0_expected, tokenToString(SyntaxKind.LineTerminatorToken));
         }
 
@@ -619,7 +619,7 @@ export class Checker {
                 case SyntaxKind.ElementOfToken:
                 case SyntaxKind.LessThanExclamationToken:
                 case SyntaxKind.NotAnElementOfToken:
-                    return this.reportGrammarError(node.operatorToken.end, Diagnostics._0_expected, tokenToString(SyntaxKind.OpenBraceToken));
+                    return this.reportGrammarError(node.operatorToken.end, Diagnostics._0_expected, formatList([SyntaxKind.OpenBraceToken, SyntaxKind.Nonterminal]));
             }
         }
 
@@ -628,10 +628,9 @@ export class Checker {
             case SyntaxKind.EqualsEqualsToken:
             case SyntaxKind.ExclamationEqualsToken:
             case SyntaxKind.NotEqualToToken:
-                if (node.lookahead.kind !== SyntaxKind.SymbolSpan) {
+                if (!isTerminal(node.lookahead)) {
                     return this.reportGrammarErrorForNode(node, Diagnostics._0_expected, formatList([
                         SyntaxKind.Terminal,
-                        SyntaxKind.Identifier,
                         SyntaxKind.UnicodeCharacterLiteral
                     ]));
                 }
@@ -642,14 +641,33 @@ export class Checker {
             case SyntaxKind.ElementOfToken:
             case SyntaxKind.LessThanExclamationToken:
             case SyntaxKind.NotAnElementOfToken:
-                if (node.lookahead.kind !== SyntaxKind.SymbolSet) {
-                    return this.reportGrammarErrorForNode(node, Diagnostics._0_expected, tokenToString(SyntaxKind.OpenBraceToken));
+                if (!isNonterminalOrSymbolSet(node.lookahead)) {
+                    return this.reportGrammarErrorForNode(node, Diagnostics._0_expected, formatList([
+                        SyntaxKind.OpenBraceToken,
+                        SyntaxKind.Nonterminal
+                    ]));
                 }
 
                 break;
         }
 
         return false;
+
+        function isTerminal(node: SymbolSpan | SymbolSet) {
+            if (node.kind !== SyntaxKind.SymbolSpan) return false;
+            switch (node.symbol.kind) {
+                case SyntaxKind.Terminal:
+                case SyntaxKind.UnicodeCharacterLiteral:
+                    return true;
+            }
+            return false;
+        }
+
+        function isNonterminalOrSymbolSet(node: SymbolSpan | SymbolSet) {
+            return node.kind === SyntaxKind.SymbolSpan
+                ? node.symbol.kind === SyntaxKind.Nonterminal
+                : node.kind === SyntaxKind.SymbolSet;
+        }
     }
 
     private checkSymbolSet(node: SymbolSet): void {
diff --git a/src/lib/nodes.ts b/src/lib/nodes.ts
index 71dae19..209f3d5 100644
--- a/src/lib/nodes.ts
+++ b/src/lib/nodes.ts
@@ -15,7 +15,7 @@
  */
 import { Dictionary, Range, Position, TextRange } from "./core";
 import { LineMap } from "./diagnostics";
-import { SyntaxKind } from "./tokens";
+import { SyntaxKind, ProseFragmentLiteralKinds, MetaKinds } from "./tokens";
 import { SymbolTable } from "./symbols";
 import { metadata, getPropertyMetadata } from "./metadata";
 
@@ -49,14 +49,14 @@ export namespace NodeEdge {
     }
 }
 
-export class Node implements TextRange {
-    public kind: SyntaxKind;
+export class Node<TKind extends SyntaxKind = SyntaxKind> implements TextRange {
+    public kind: TKind;
     public id: number = ++nextNodeId;
     public pos: number;
     public end: number;
     private _edges: NodeEdge[];
 
-    constructor(kind: SyntaxKind) {
+    constructor(kind: TKind) {
         this.kind = kind;
     }
 
@@ -65,7 +65,7 @@ export class Node implements TextRange {
     }
 }
 
-export class StringLiteral extends Node implements TextContent {
+export class StringLiteral extends Node<SyntaxKind.StringLiteral> implements TextContent {
     public text: string;
 
     constructor(text: string) {
@@ -75,7 +75,7 @@ export class StringLiteral extends Node implements TextContent {
     }
 }
 
-export class Identifier extends Node implements TextContent {
+export class Identifier extends Node<SyntaxKind.Identifier> implements TextContent {
     public text: string;
 
     constructor(text: string) {
@@ -85,16 +85,16 @@ export class Identifier extends Node implements TextContent {
     }
 }
 
-export class LexicalSymbol extends Node {
+export class LexicalSymbol<TKind extends SyntaxKind = SyntaxKind> extends Node<TKind> {
 }
 
-export class PrimarySymbol extends LexicalSymbol {
+export class PrimarySymbol<TKind extends SyntaxKind = SyntaxKind> extends LexicalSymbol<TKind> {
 }
 
-export class OptionalSymbol extends PrimarySymbol {
+export class OptionalSymbol<TKind extends SyntaxKind = SyntaxKind> extends PrimarySymbol<TKind> {
     @edge questionToken: Node;
 
-    constructor(kind: SyntaxKind, questionToken: Node) {
+    constructor(kind: TKind, questionToken: Node) {
         super(kind);
 
         this.questionToken = questionToken;
@@ -109,7 +109,7 @@ export class OptionalSymbol extends PrimarySymbol {
     }
 }
 
-export class UnicodeCharacterLiteral extends OptionalSymbol implements TextContent {
+export class UnicodeCharacterLiteral extends OptionalSymbol<SyntaxKind.UnicodeCharacterLiteral> implements TextContent {
     public text: string;
 
     constructor(text: string, questionToken: Node) {
@@ -119,7 +119,7 @@ export class UnicodeCharacterLiteral extends OptionalSymbol implements TextConte
     }
 }
 
-export class UnicodeCharacterRange extends LexicalSymbol {
+export class UnicodeCharacterRange extends LexicalSymbol<SyntaxKind.UnicodeCharacterRange> {
     @edge left: UnicodeCharacterLiteral;
     @edge throughKeyword: Node;
     @edge right: UnicodeCharacterLiteral;
@@ -132,7 +132,7 @@ export class UnicodeCharacterRange extends LexicalSymbol {
     }
 }
 
-export class ButNotSymbol extends LexicalSymbol {
+export class ButNotSymbol extends LexicalSymbol<SyntaxKind.ButNotSymbol> {
     @edge left: LexicalSymbol;
     @edge butKeyword: Node;
     @edge notKeyword: Node;
@@ -147,7 +147,7 @@ export class ButNotSymbol extends LexicalSymbol {
     }
 }
 
-export class Terminal extends OptionalSymbol implements TextContent {
+export class Terminal extends OptionalSymbol<SyntaxKind.Terminal> implements TextContent {
     public text: string;
 
     constructor(text: string, questionToken: Node) {
@@ -157,7 +157,7 @@ export class Terminal extends OptionalSymbol implements TextContent {
     }
 }
 
-export class TerminalList extends Node {
+export class TerminalList extends Node<SyntaxKind.TerminalList> {
     @edge terminals: Terminal[];
 
     constructor(terminals: Terminal[] = []) {
@@ -167,7 +167,7 @@ export class TerminalList extends Node {
     }
 }
 
-export class SymbolSet extends Node {
+export class SymbolSet extends Node<SyntaxKind.SymbolSet> {
     @edge openBraceToken: Node;
     @edge elements: SymbolSpan[];
     @edge closeBraceToken: Node;
@@ -181,11 +181,11 @@ export class SymbolSet extends Node {
     }
 }
 
-export class Assertion extends LexicalSymbol {
+export class Assertion<TKind extends SyntaxKind = SyntaxKind> extends LexicalSymbol<TKind> {
     @edge openBracketToken: Node;
     @edge closeBracketToken: Node;
 
-    constructor(kind: SyntaxKind, openBracketToken: Node, closeBracketToken: Node) {
+    constructor(kind: TKind, openBracketToken: Node, closeBracketToken: Node) {
         super(kind);
 
         this.openBracketToken = openBracketToken;
@@ -193,7 +193,7 @@ export class Assertion extends LexicalSymbol {
     }
 }
 
-export class EmptyAssertion extends Assertion {
+export class EmptyAssertion extends Assertion<SyntaxKind.EmptyAssertion> {
     @edge openBracketToken: Node;
     @edge emptyKeyword: Node;
     @edge closeBracketToken: Node;
@@ -205,7 +205,7 @@ export class EmptyAssertion extends Assertion {
     }
 }
 
-export class LookaheadAssertion extends Assertion {
+export class LookaheadAssertion extends Assertion<SyntaxKind.LookaheadAssertion> {
     @edge openBracketToken: Node;
     @edge lookaheadKeyword: Node;
     @edge operatorToken: Node;
@@ -221,7 +221,7 @@ export class LookaheadAssertion extends Assertion {
     }
 }
 
-export class LexicalGoalAssertion extends Assertion {
+export class LexicalGoalAssertion extends Assertion<SyntaxKind.LexicalGoalAssertion> {
     @edge openBracketToken: Node;
     @edge lexicalKeyword: Node;
     @edge goalKeyword: Node;
@@ -237,7 +237,7 @@ export class LexicalGoalAssertion extends Assertion {
     }
 }
 
-export class NoSymbolHereAssertion extends Assertion {
+export class NoSymbolHereAssertion extends Assertion<SyntaxKind.NoSymbolHereAssertion> {
     @edge openBracketToken: Node;
     @edge noKeyword: Node;
     @edge symbols: PrimarySymbol[];
@@ -253,7 +253,7 @@ export class NoSymbolHereAssertion extends Assertion {
     }
 }
 
-export class ParameterValueAssertion extends Assertion {
+export class ParameterValueAssertion extends Assertion<SyntaxKind.ParameterValueAssertion> {
     @edge openBracketToken: Node;
     @edge operatorToken: Node;
     @edge name: Identifier;
@@ -267,7 +267,7 @@ export class ParameterValueAssertion extends Assertion {
     }
 }
 
-export class ProseAssertion extends Assertion {
+export class ProseAssertion extends Assertion<SyntaxKind.ProseAssertion> {
     @edge openBracketToken: Node;
     @edge fragments: ProseFragment[];
     @edge closeBracketToken: Node;
@@ -278,7 +278,7 @@ export class ProseAssertion extends Assertion {
     }
 }
 
-export class ProseFragmentLiteral extends Node implements TextContent {
+export class ProseFragmentLiteral<TKind extends ProseFragmentLiteralKinds = ProseFragmentLiteralKinds> extends Node<SyntaxKind> implements TextContent {
     text: string;
 
     constructor(kind: SyntaxKind, text: string) {
@@ -289,7 +289,7 @@ export class ProseFragmentLiteral extends Node implements TextContent {
 
 export type ProseFragment = ProseFragmentLiteral | Terminal | Nonterminal;
 
-export class Argument extends Node {
+export class Argument extends Node<SyntaxKind.Argument> {
     @edge operatorToken: Node;
     @edge name: Identifier;
 
@@ -301,7 +301,7 @@ export class Argument extends Node {
     }
 }
 
-export class ArgumentList extends Node {
+export class ArgumentList extends Node<SyntaxKind.ArgumentList> {
     @edge openParenToken: Node;
     @edge elements: Argument[];
     @edge closeParenToken: Node;
@@ -315,7 +315,7 @@ export class ArgumentList extends Node {
     }
 }
 
-export class Nonterminal extends OptionalSymbol {
+export class Nonterminal extends OptionalSymbol<SyntaxKind.Nonterminal> {
     @edge name: Identifier;
     @edge argumentList: ArgumentList;
 
@@ -327,7 +327,7 @@ export class Nonterminal extends OptionalSymbol {
     }
 }
 
-export class Prose extends LexicalSymbol {
+export class Prose extends LexicalSymbol<SyntaxKind.Prose> {
     @edge greaterThanToken: Node;
     @edge fragments: ProseFragment[];
 
@@ -339,7 +339,7 @@ export class Prose extends LexicalSymbol {
     }
 }
 
-export class OneOfSymbol extends LexicalSymbol {
+export class OneOfSymbol extends LexicalSymbol<SyntaxKind.OneOfSymbol> {
     @edge oneKeyword: Node;
     @edge ofKeyword: Node;
     @edge symbols: LexicalSymbol[];
@@ -353,7 +353,7 @@ export class OneOfSymbol extends LexicalSymbol {
     }
 }
 
-export class SymbolSpan extends Node {
+export class SymbolSpan extends Node<SyntaxKind.SymbolSpan> {
     @edge symbol: LexicalSymbol;
     @edge next: SymbolSpan;
 
@@ -365,7 +365,7 @@ export class SymbolSpan extends Node {
     }
 }
 
-export class LinkReference extends Node {
+export class LinkReference extends Node<SyntaxKind.LinkReference> {
     public text: string;
 
     constructor(text: string) {
@@ -375,7 +375,7 @@ export class LinkReference extends Node {
     }
 }
 
-export class RightHandSide extends Node {
+export class RightHandSide extends Node<SyntaxKind.RightHandSide> {
     @edge head: SymbolSpan;
     @edge reference: LinkReference;
 
@@ -387,7 +387,7 @@ export class RightHandSide extends Node {
     }
 }
 
-export class RightHandSideList extends Node {
+export class RightHandSideList extends Node<SyntaxKind.RightHandSideList> {
     @edge openIndentToken: Node;
     @edge elements: RightHandSide[];
     @edge closeIndentToken: Node;
@@ -401,7 +401,7 @@ export class RightHandSideList extends Node {
     }
 }
 
-export class OneOfList extends Node {
+export class OneOfList extends Node<SyntaxKind.OneOfList> {
     @edge openIndentToken: Node;
     @edge oneKeyword: Node;
     @edge ofKeyword: Node;
@@ -419,7 +419,7 @@ export class OneOfList extends Node {
     }
 }
 
-export class Parameter extends Node {
+export class Parameter extends Node<SyntaxKind.Parameter> {
     @edge name: Identifier;
 
     constructor(name: Identifier) {
@@ -429,7 +429,7 @@ export class Parameter extends Node {
     }
 }
 
-export class ParameterList extends Node {
+export class ParameterList extends Node<SyntaxKind.ParameterList> {
     @edge openParenToken: Node;
     @edge elements: Parameter[];
     @edge closeParenToken: Node;
@@ -443,10 +443,10 @@ export class ParameterList extends Node {
     }
 }
 
-export class SourceElement extends Node {
+export class SourceElement<TKind extends SyntaxKind = SyntaxKind> extends Node<TKind> {
 }
 
-export class Production extends SourceElement {
+export class Production extends SourceElement<SyntaxKind.Production> {
     @edge name: Identifier;
     @edge colonToken: Node;
     @edge parameterList: ParameterList;
@@ -462,16 +462,16 @@ export class Production extends SourceElement {
     }
 }
 
-export abstract class MetaElement extends SourceElement {
+export abstract class MetaElement<TKind extends MetaKinds = MetaKinds> extends SourceElement<TKind> {
     @edge atToken: Node;
 
-    constructor(kind: SyntaxKind, atToken: Node) {
+    constructor(kind: TKind, atToken: Node) {
         super(kind);
         this.atToken = atToken;
     }
 }
 
-export class Import extends MetaElement {
+export class Import extends MetaElement<SyntaxKind.Import> {
     @edge importKeyword: Node;
     @edge path: StringLiteral;
 
@@ -482,7 +482,7 @@ export class Import extends MetaElement {
     }
 }
 
-export class Define extends MetaElement {
+export class Define extends MetaElement<SyntaxKind.Define> {
     @edge defineKeyword: Node;
     @edge key: Identifier;
     @edge valueToken: Node;
@@ -495,7 +495,7 @@ export class Define extends MetaElement {
     }
 }
 
-export class SourceFile extends Node {
+export class SourceFile extends Node<SyntaxKind.SourceFile> {
     public filename: string;
     public text: string;
     @edge elements: SourceElement[];
diff --git a/src/lib/tokens.ts b/src/lib/tokens.ts
index 6e6890b..6f561f3 100644
--- a/src/lib/tokens.ts
+++ b/src/lib/tokens.ts
@@ -264,6 +264,16 @@ export enum SyntaxKind {
     LastPunctuation = LessThanMinusToken,
 }
 
+export type ProseFragmentLiteralKinds =
+    | SyntaxKind.ProseFull
+    | SyntaxKind.ProseHead
+    | SyntaxKind.ProseMiddle
+    | SyntaxKind.ProseTail;
+
+export type MetaKinds =
+    | SyntaxKind.Import
+    | SyntaxKind.Define;
+
 const textToToken = new Dictionary({
     "but": SyntaxKind.ButKeyword,
     "define": SyntaxKind.DefineKeyword,