SWI-Prolog allows for nesting /* ... */ comments. Where
the ISO standard accepts /* ... /* ... */ as a comment,
SWI-Prolog will search for a terminating */. This is useful
if some code with /* ... */ comment statements in it should
be commented out. This modification also avoids unintended commenting in
the example below, where the closing */ of the first
comment has been forgotten.27Recent
copies of GCC give a style warning if /* is encountered in
a comment, which suggests that this problem has been recognised more
widely.
/* comment code /* second comment */ code