What are the advantages of a codified constitution?

A codified constitution is essentially a type of constitution that is written in a single document, outlining the rules for how power is exercised in the country. There are several factors in favour of a codified constitution in the UK. The most important is that it removes the 'elective dictatorship': the government's ability to use its majority to push through whatever laws it likes in parliament. This is because in the UK, parliament is sovereign, rather than a single, rigid document. This prevents the government from changing the constitution however it sees fit by establishing rules it has to follow in order to change parts of the constitution. Another advantage is that a codified constitution would prevent the government from overreaching its executive powers by holding it to account to clear rules. The government's attempt to not publish legal advice on its Brexit plans, are an example for this.