That's the primary difference between common law and civil law countries.
In Germany for example, there are regular laws (if you need to know what's legal and what not, these are the ones you read) and change laws (Änderungsgesetze), which usually read like
"Law XYZ, Paragraph 5a, Sentence 3 is changed to read as follows: '...', Sentence 7 is appended with '...', Sentence 8 is removed"
So at any time, you've got a clear set of laws that apply.
In Germany for example, there are regular laws (if you need to know what's legal and what not, these are the ones you read) and change laws (Änderungsgesetze), which usually read like
"Law XYZ, Paragraph 5a, Sentence 3 is changed to read as follows: '...', Sentence 7 is appended with '...', Sentence 8 is removed"
So at any time, you've got a clear set of laws that apply.