The code compiles but results in a runtime crash - presumably because
the remove-if-not function calls the lambda with a single argument but
the lambda declared doesn't take one.
Adding the (cons x()) sorts this out as you suggested.
I think I prefer the (declare (ignore x)) declaration though as this
just makes the code intent that bit clearer - to me anyway.
On Jan 28, 9:59 pm, Christopher Allen-Poole <christoph...@allen-