src/vs/workbench/contrib/preferences/browser/settingsTree.ts/settingMatches
function settingMatches(s: ISetting, pattern: string): boolean {
	let regExp = settingPatternCache.get(pattern);
	if (!regExp) {
		regExp = createSettingMatchRegExp(pattern);
		settingPatternCache.set(pattern, regExp);
	}

	return regExp.test(s.key);
}