add library, tsconfig.base.json

assets/util.ts

@@ -45,7 +45,7 @@ export const doMapKeypress = (
 export function shuffle<T>(a: T[]) {
   for (let i = a.length - 1; i > 0; i--) {
     const j = Math.floor(Math.random() * (i + 1))
-    ;[a[i], a[j]] = [a[j], a[i]]
+    ;[a[i], a[j]] = [a[j]!, a[i]!]
   }
   return a
 }
@@ -60,7 +60,7 @@ export function sample<T>(arr: T[], size: number): T[] {
     outN.push(...allN.splice(Math.floor(Math.random() * allN.length), 1))
   }
 
-  return outN.map((n) => arr[n])
+  return outN.map((n) => arr[n]!)
 }
 
 export function capitalize(s: string): string {
@@ -72,7 +72,7 @@ export function capitalize(s: string): string {
   }
 
   if (!s) return s
-  return s[0].toLocaleUpperCase() + s.substr(1)
+  return s[0]!.toLocaleUpperCase() + s.substr(1)
 }
 
 export function jsonClone<T>(o: T): T {