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Evaluates a block of Perl code and sets $_ to each
element of the list in turn. If BLOCK is
true, first returns the first element. If
BLOCK never returns true, or
@list has no items,
then first returns undef. Note
that first doesn't necessarily
return the first item in a list. Consider the following:

my @ll = qw(1 2 3);
my $fir = first { $_ > 1 } @ll;
print "$fir\n"; # Prints '2', since as 2 is the first item
# in BLOCK that's > 1

Returns the entry in the list with the highest numerical value. If
the list is empty, max returns
undef:

my @ll = qw(100 294 2 4 95 73);
my $max_num = max @ll;
print "$max_num\n"; # Prints '294'

Similar to max, except that
maxstr treats all list items as strings.
maxstr will return the "highest
string" as determined by the gt
operator. As always, if list is empty, maxstr
returns undef.

my @ll = qw(1 3 5 nate Person pizza man carl_everett dinosaur);
my $max_s = maxstr(@ll);
print "$max_s\n"; # Prints 'pizza'

Returns the lowest numerical value. If the list is
empty, min returns undef.

Treats all list items as strings, but returns the
"lowest string" as determined by
the lt operator. If the list is empty,
minstr returns undef.

Literally "reduces"
@list by calling
BLOCK until there are no more items to
operate on in @list.
reduce sets $a and
$b for each operation in
BLOCK and returns the reduced list as a
scalar. If @list is
0, BLOCK is not
executed, and
$list[0]
is returned. If @list is empty, then
reduce returns undef.

You can sum and concatenate a list using reduce
like so:

my $sum_of_list = reduce { $a + $b } @ll; # sum
my $concat_list = reduce { $a . $b } @ll; # concat

Returns list items in random order.

Returns the sum of all items in the list. Note that
sum deals only with numerical list items and will
ignore any other list items. For example:

my @ll = qw(1 3 5 nate Person pizza man carl_everett dinosaur 6.54);
my $sum_of_list = sum(@ll);
print "$sum_of_list\n"; # Prints '15.54'

8.139. lib		8.141. locale