Non-comp clause in UK

Does anyone know about these non-competition clauses in UK law?
by what i gather, in US these clauses have to come with some compensation for the designer, during the period stated in the contract.
What about Uk law?

It depends on the scenario… if you’re working for a company full time that makes you sign one then I think it’s fair. If they ask you to sign one where it says you can’t work for a competitor for x amount of months after you leave then it won’t stand up in court because it restricts you from plying your trade and so making a living… the government wouldn’t want to miss out on all those lucrative tax dollars/pounds.

If you are freelance and you’re asked to sign one then you better hope they have a lot of work coming your way or you’ll be buggered. As a freelancer I have never been asked to sign one, it would essentially make me an employee.