isIdentStartCodePoint = cc =>
	(cc >= CC_LOWER_A && cc <= CC_LOWER_Z) ||
	(cc >= CC_UPPER_A && cc <= CC_UPPER_Z) ||
	cc === CC_LOW_LINE ||
	cc >= 0x80
ident-start code point

A letter, a non-ASCII code point, or U+005F LOW LINE (_).
@param {number} cc char code
@returns {boolean} true, if cc is a start code point of an identifier