Only compute stc fields if not present

mik-jozef · Nov 17, 2023 · eed907b · eed907b
1 parent ad9c2cd
commit eed907b
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/src/pattern/match.ts b/src/pattern/match.ts
@@ -98,7 +98,7 @@ export abstract class MatchBase extends CompositePattern {
 
     grammar.cachedRuleSources.set(stc, nt);
 
-    stc.fields = CompositePattern.getFields(stc.pattern);
+    stc.fields ??= CompositePattern.getFields(stc.pattern);
 
     CompositePattern.toGrammarRule(stc.pattern, grammar, stc.name, nt);
 
@@ -116,7 +116,7 @@ export abstract class MatchBase extends CompositePattern {
       this.match.pattern instanceof CompositePattern &&
         this.match.pattern.collectSyntaxTreeClasses(map);
 
-      this.match.fields = CompositePattern.getFields(this.match.pattern);
+      this.match.fields ??= CompositePattern.getFields(this.match.pattern);
     }
 
     this.match instanceof CompositePattern &&