Use a standard british keyboard[1]. It is a pain using the Mac "british" keyboard for programming in my experience.
[1] https://commons.wikimedia.org/wiki/File:KB_United_Kingdom.sv...
[1] https://commons.wikimedia.org/wiki/File:KB_United_Kingdom.sv...
It also doesn't have the wonderful set of Alt+ combinations as the Mac British layout for typing various types of diacritics, widths of dashes, Greek letters, mathematical symbols, opening and closing quotes, and other things. PC layout users are stuck with acute accents, the Euro symbol, and nothing else.
Luckily, the Mac "British - PC" layout (not the same as the actual British PC layout) does include the extra Alt+ combos.
I'm not sure why anyone would find the Mac British layout difficult to program with. It's closer to the US layout than the PC British layout. I suppose # requiring Alt might be bothersome, but # isn't a symbol used that frequently in programming, and Alt+3 is not that difficult to type.
Also, I use # loads every day for c++ macros, and #if 0 blocks.
Apple's had their own layout for literally decades. There wasn't a standard back then.
> Having always used a standard british keyboard, the subtle differences, e.g. location of \, #, ", `, ~, really slow me down.
You can adjust to it pretty quickly.