src/vs/editor/common/core/wordHelper.ts/createWordRegExp
function createWordRegExp(allowInWords: string = ''): RegExp {
	let source = '(-?\\d*\\.\\d\\w*)|([^';
	for (const sep of USUAL_WORD_SEPARATORS) {
		if (allowInWords.indexOf(sep) >= 0) {
			continue;
		}
		source += '\\' + sep;
	}
	source += '\\s]+)';
	return new RegExp(source, 'g');
}