export function convertToUnit (str: string | number | null | undefined, unit = 'px'): string | undefined {
    if (str == null || str === '') {
        return undefined
    } else if (isNaN(+str!)) {
        return String(str)
    } else {
        return `${Number(str)}${unit}`
    }
}

export function stopAndPrevent (e: any) {
    e.cancelable !== false && e.preventDefault()
    e.stopPropagation()
}