Function isInAstralSet

browser.js:17776–17784

(code, set)

// assumption is that looking up astral identifier characters is
// rare.
function isInAstralSet(code, set) {
  var pos = 0x10000;
  for (var i = 0; i < set.length; i += 2) {
    pos += set[i];
    if (pos > code) { return false }
    pos += set[i + 1];
    if (pos >= code) { return true }
  }
}

// Test whether a given character code starts an identifier.