// conv.int itos(i: int): string // Produce a formatted version of i. stoi(s: string, err: int): int // Parse s as a formatted integer. // Return err if the string could not be parsed. itoc(i: int): string // Produce a string containing the single character whose ASCII code is i. atos(a: array[int]): string // Produce a string containing the characters whose ASCII codes are in a, // in proper sequence stoa(s: string): array[int] // produce an array containing the ASCII codes of all the characters in s, // in proper sequence