Undocumented continuation line syntax?

[boriel]

Thank you, Boriel, and don't worry about the delay.

So ZXBasic has a fully featured C-like preprocessor? That's very useful, and those are already well documented.

Well, "fully featured" depends on the standar and version you follow. e.g. CPP from GNU C has many non-standar powerful features I've find very hard to mimic (I prefer to concentrate the efforts in the compiler). But other than that, I think it's a quite complete preprocessor. E.g. you can define macros to be used as inline functions (which are slightly faster), etc...
There are many examples in the compiler library/ directory and in this forum, if I recall correctly.