Regex que verifica se uma data é válida segundo as regras do calendário gregoriano

Encontra as rimas buscadas na poesia de Camões

Matches exactly two arrays of number literals separated by a multiplication character, where that multiplication character is either an asterisk or an x, and an array is started with a left square bracket, and whose contents are separated by commas, and which ends with a right square bracket. Unimp...

/\..{0,}? /

This regex is created to match Guard IDs