function checkForAcceptableEscapeInString(char, nodeSource, codeUnits) {
	const firstIndex = char.start;
	const lastIndex = char.end - 1;
	const start = codeUnits[firstIndex].start;
	const end = codeUnits[lastIndex].end;
	const charSource = nodeSource.slice(start, end);

	return checkForAcceptableEscape(char, charSource);
}
Checks whether a specified regexpp character is represented as an acceptable escape sequence.
This function works with characters that are produced by a string or template literal.
It requires the source text and the CodeUnit list of the literal to be known.
@param {Character} char Character to check.
@param {string} nodeSource Source text of the string or template literal that produces the character.
@param {CodeUnit[]} codeUnits List of CodeUnit objects of the literal that produces the character.
@returns {boolean} Whether the specified regexpp character is represented as an acceptable escape sequence.