export const SESSION_ENTRY_REGEXP = /^([a-zA-Z]+)=([a-z0-9-]+)$/ export const SESSION_ENTRY_SEPARATOR = '&' export function isValidSessionString(sessionString: string | undefined | null): sessionString is string { return ( !!sessionString && (sessionString.indexOf(SESSION_ENTRY_SEPARATOR) !== -1 || SESSION_ENTRY_REGEXP.test(sessionString)) ) }