How do we properly handle apostrophes in IfcLabel?

We have an IfcLabel which contains an apostrophe and it’s breaking at least two viewers that we know of. How do we escape “special” characters in IFC with a guarantee that viewers will handle un-escaping?

Hey @ian,
I know we have only a couple resources that address this:

Maybe @Evandro, @GeorgDangl, @linhard, or @mweise can help? I think this issue might be part of certification.

For clarity:

From 10303 21 we can read:

6.4.3.1 String structure

… Within a string, a single apostrophe shall be encoded as two consecutive apostrophes

I must say that I’ve personally never have encountered issues with this in any implementation I’m aware of.

Thanks @aothms.

As far as I can tell, you mean ISO 10303 part 21, which is a paywalled iso standard that a developer can’t access. Yes, they could spend the money and buy the standard, and look up the section on string encoding, but they’re probably not going to do it.

I agree, I’ve created an issue to improve IfcLabel/IfcText etc. · Issue #476 · buildingSMART/IFC4.3.x-development · GitHub

For reference, this is a great link :slight_smile: https://www.steptools.com/stds/step/IS_final_p21e3.html#clause-6-4-3