function patternMatcher(str, regexp) {
    const regexpClone = new RegExp(
        regexp.source,
        regexp.flags ||
            (regexp.global ? 'g' : '') +
            (regexp.ignoreCase ? 'i' : '') +
            (regexp.multiline ? 'm' : '') +
            (regexp.dotAll ? 's' : '') +
            (regexp.unicode ? 'u' : '') +
            (regexp.sticky ? 'y' : '')
    )
    regexpClone.lastIndex = 0
    const matches = []
    let match
    if (regexpClone.global) {
        while(match = regexpClone.exec(str)) {
            matches.push(match)
        }
    }
    else {
        if (match = regexpClone.exec(str)) {
            matches.push(match)
        }
    }
    return matches
}