Postgres' lexer

Hi!

I'm currently fooling around with Postgres's parser, and I must admit
some things puzzle me completely. Please tell me what these things in
lexer stand for:

{operator}/-[\.0-9] {
yylval.str = pstrdup((char*)yytext);
return Op;
}
Is it an operator followed by mandatory '-' and (dot or digit) ?

And what this stands for:

{identifier}/{space}*-{number}

What's the meaning of all these?

--
Leon.
---------
"This may seem a bit weird, but that's okay, because it is weird." -
Perl manpage.