On 27 Aug 2002, Aaron Sherman wrote:
: I just wrote this code in Perl5:
:
: $stuff = (defined($1)?$1:$2) if /^\s*(?:"(.*?)"|(\S+))/;
:
: This is a common practice for me when I parse configuration and data
: files whose formats I define. It's nice to be able to quote fields that
: have spaces, and this is an easy way to parse the result.
:
: In Perl6, it looks like what I would like here is very close, but I'm
: not sure. Certainly, I could do:
:
: $stuff = ($1 // $2) if m{^\s*["(.*?)"|(\S+)]};
:
: But I would far prefer:
:
: $stuff = $field if m{^\s*[
: "(.*?)" {let $field=$1} |
: (\S+) {let $field=$2}]};
:
: even though it's longer.
That seems like a lot of extra work. I'd prefer to see something like:
my stuff;
m{^\s*[
"$stuff:=(.*?)" |
$stuff:=(\S+)
]};
: Is this possible, or does the underlying implementation of hypothetical
: variables pretty much rule it out?
I don't see any particular reason why a top-level regex can't refer to
variables in the surrounding scope, either by default, or via a :modifier
of some sort. It's only down in the sub-rules that we have to make sure
there's a hash to poke such hypotheticals into.
Larry
