Message
RangeError: {0} is not a valid code point (Firefox)
RangeError: Invalid code point {0} (Chrome)
Error type
What went wrong?
The String.fromCodePoint() method accepts valid code points only.
A code point is a value in the Unicode codespace; that is, the range of integers from 0 to 0x10FFFF.
Using NaN values, negative Integers (-1), non-Integers (3.14), or values larger than 0x10FFFF (1114111) won't work with this method.
Examples
Invalid cases
String.fromCodePoint('_');      // RangeError
String.fromCodePoint(Infinity); // RangeError
String.fromCodePoint(-1);       // RangeError
String.fromCodePoint(3.14);     // RangeError
String.fromCodePoint(3e-2);     // RangeError
String.fromCodePoint(NaN);      // RangeError
Valid cases
String.fromCodePoint(42); // "*" String.fromCodePoint(65, 90); // "AZ" String.fromCodePoint(0x404); // "\u0404" String.fromCodePoint(0x2F804); // "\uD87E\uDC04" String.fromCodePoint(194564); // "\uD87E\uDC04" String.fromCodePoint(0x1D306, 0x61, 0x1D307) // "\uD834\uDF06a\uD834\uDF07"