isHighSurrogate static method

bool isHighSurrogate(int value)

Returns true iff the given value is a valid UTF-16 high (first) surrogate. The value must be a UTF-16 code unit, meaning it must be in the range 0x0000-0xFFFF.

See also:

• https://en.wikipedia.org/wiki/UTF-16#Code_points_from_U+010000_to_U+10FFFF
• isLowSurrogate, which checks the same thing for low (second) surrogates.

Implementation

static bool isHighSurrogate(int value) {
  assert(_isUTF16(value));
  return value & 0xFC00 == 0xD800;
}