Interesting things, dress codes.

On the face of it, the phrase describes a bunch of rules about what you can and can't wear in a specific setting. But, of course, code has another meaning: riddle, enigma, something to be deciphered. And how.

For me, decoding the washing instructions on my pants is taxing enough, so I tend to baulk at anything involving hard-to-fathom sartorial injunctions. Besides, sometimes the "code" isn't even written down, it's an entirely subjective decision made by, say, a bouncer. Which is why I was once denied entry to All Bar One for wearing dungarees. Apparently All Bar One have a no dungarees policy. Who knew?

We've seen similar stories played out in the news recently. Firstly at the Cannes film festival, where the wife of British director Asif Kapadia was one of several women allegedly told she couldn't enter a red carpet event in flat shoes. Then last week in Canada, where #CropTopDay began trending after a Toronto student was told not to attend school wearing one of these midriff-baring items. Soon a 4000-signature petition had been presented to the school demanding a change in the dress code, while the case itself made headlines around the world. Even more headlines and outrage met the Cannes flat shoe ban, to the extent that festival organisers had to deny high heels were ever obligatory on the red carpet.

I came across another dress code recently when the idea of sending a family member to Claridges for tea as a birthday present turned up the London hotel's strict dress code. On the list of proscribed items: shorts, vests, sportswear, flip-flops, ripped jeans and baseball caps. Our intended recipient isn't likely to don any of those, but I'm fairly certain that if One Direction turned up for a pot of Lapsang and a fruit scone wearing some or all of that lot, they'd be shown the menu not the door. So it seems a dress code is only a dress code until someone complains about it. Or unless you're more famous than the wife of British director Asif Kapadia.

But even those like me who try to live their lives unencumbered by dress codes - I steer clear of Cannes, Claridges and crop tops for exactly that reason - have to brush up against them occasionally. For instance, my son asked me recently what exactly was meant by "smart casual". I don't know why. Maybe he'd been opening next door's wrongly-delivered post again and come across the phrase on a gold-embossed invitation such as he never sees on his parents' mantle-piece.

I told him it was a mixture of smart and casual, an explanation he met with a "Yeah, obviously" roll of his eyes. What I should have said is: "Don't worry about it. You'll never need to know because you're going to grow up to be a convention-flouting rock star for whom things like dress codes will never apply. Like Harry Styles".

Instead I gave him my best Attention! Sound Parental Advice Coming Atcha face and mumbled something about chinos. On reflection, I should probably have added: "And definitely no dungarees."