> Is there a Perl function that returns the index of a given element in an
array? For example:
my @list = q( apple banana pear grapefruit);
my $look4 = "banana";
my $ndx = somefunc( $look4, @list ); # sets $ndx to 1
$look4 = "monkeywrench";
$ndx = somefunc( $look4, @list); # sets $ndx to -1, or maybe undef?
Usually, looking for the index is a sign of a data structure issue. Arrays
are, by nature, not data addressable, that's what hashes are for. A trick
would be to transform it into a hash (w/ the index as the value) and look
that way but that's only elegant in the eye of certain transformer folks.
You can *just* determine if it's in there by grep:
my $in_there = grep { /^banana$/ } @list;
Or you could, if you hadn't tricked us:
my @list = q( apple banana pear grapefruit);
returns a single string i.e
$list[0] eq ' apple banana pear grapfruit';
You want "quote word" ;->
my @list = qw( apple banana pear grapefruit);
anyway. You can turn it into a hash:
my $in_there = grep { /^$look4$/ } @list;
my $cnt = 0;
my %at_where = map { $_ => $cnt++; } @list;
print "Yep $at_where{$look4}\n" if $in_there;
You can try a map in a void context:
my $at_where = 0;
my $cnt = 0;
map { $cnt++; $at_where = $cnt -1 if /^$look4$/ ; } @list;
but, as LW says "I wouldn't want to map anybody in a void context" ... or
words to that effect.
a
Andy Bach
Systems Mangler
Internet: [EMAIL PROTECTED]
VOICE: (608) 261-5738 FAX 264-5932
Wire telegraph is a kind of a very, very long cat. You pull his tail in
New York and his head is meowing in Los Angeles. And radio operates
exactly the same way. The only difference is that there is no cat.
--Albert Einstein (explaining radio)
_______________________________________________
ActivePerl mailing list
[email protected]
To unsubscribe: http://listserv.ActiveState.com/mailman/mysubs
