Simplified Unicode string handling logic in TypeScript code thanks to ES6 features.

typescript-javascript/qrcodegen-input-demo.ts

@@ -127,17 +127,11 @@ namespace app {
 		// Returns the number of Unicode code points in the given UTF-16 string.
 		function countUnicodeChars(str: string): number {
 			let result: number = 0;
-			for (let i = 0; i < str.length; i++, result++) {
-				const c: number = str.charCodeAt(i);
-				if (c < 0xD800 || c >= 0xE000)
-					continue;
-				else if (0xD800 <= c && c < 0xDC00 && i + 1 < str.length) {  // High surrogate
-					i++;
-					const d: number = str.charCodeAt(i);
-					if (0xDC00 <= d && d < 0xE000)  // Low surrogate
-						continue;
-				}
+			for (const ch of str) {
+				const cc = ch.codePointAt(0) as number;
+				if (0xD800 <= cc && cc < 0xE000)
 					throw new RangeError("Invalid UTF-16 string");
+				result++;
 			}
 			return result;
 		}