fix: ensure makeMap calls are tree-shakable

2019-10-15 12:19:46 -04:00
parent 58fffcb987
commit 7de3aee317
4 changed files with 10 additions and 9 deletions
--- a/packages/shared/src/makeMap.ts
+++ b/packages/shared/src/makeMap.ts
@@ -1,7 +1,8 @@
-/**
- * Make a map and return a function for checking if a key
- * is in that map.
- */
+// Make a map and return a function for checking if a key
+// is in that map.
+//
+// IMPORTANT: all calls of this function must be prefixed with /*@__PURE__*/
+// So that rollup can tree-shake them if necessary.
 export function makeMap(
  str: string,
  expectsLowerCase?: boolean