List::MoreUtils 0.22

List::MoreUtils is a Perl module that can provide the stuff missing in List::Util.

SYNOPSIS

use List::MoreUtils qw(any all none notall true false firstidx first_index
lastidx last_index insert_after insert_after_string
apply after after_incl before before_incl indexes
firstval first_value lastval last_value each_array
each_arrayref pairwise natatime mesh zip uniq minmax);

List::MoreUtils provides some trivial but commonly needed functionality on lists which is not going to go into List::Util.

All of the below functions are implementable in only a couple of lines of Perl code. Using the functions from this module however should give slightly better performance as everything is implemented in C. The pure-Perl implementation of these functions only serves as a fallback in case the C portions of this module couldnt be compiled on this machine.

any BLOCK LIST

Returns a true value if any item in LIST meets the criterion given through BLOCK. Sets $_ for each item in LIST in turn:

print "At least one value undefined"
if any { !defined($_) } @list;

Returns false otherwise, or undef if LIST is empty.

all BLOCK LIST

Returns a true value if all items in LIST meet the criterion given through BLOCK. Sets $_ for each item in LIST in turn:

print "All items defined"
if all { defined($_) } @list;

Returns false otherwise, or undef if LIST is empty.

none BLOCK LIST

Logically the negation of any. Returns a true value if no item in LIST meets the criterion given through BLOCK. Sets $_ for each item in LIST in turn:

print "No value defined"
if none { defined($_) } @list;

Returns false otherwise, or undef if LIST is empty.

notall BLOCK LIST

Logically the negation of all. Returns a true value if not all items in LIST meet the criterion given through BLOCK. Sets $_ for each item in LIST in turn:

print "Not all values defined"
if notall { defined($_) } @list;

Returns false otherwise, or undef if LIST is empty.

true BLOCK LIST

Counts the number of elements in LIST for which the criterion in BLOCK is true. Sets $_ for each item in LIST in turn:

printf "%i item(s) are defined", true { defined($_) } @list;

false BLOCK LIST

Counts the number of elements in LIST for which the criterion in BLOCK is false. Sets $_ for each item in LIST in turn:

printf "%i item(s) are not defined", false { defined($_) } @list;

firstidx BLOCK LIST

first_index BLOCK LIST

Returns the index of the first element in LIST for which the criterion in BLOCK is true. Sets $_ for each item in LIST in turn:

my @list = (1, 4, 3, 2, 4, 6);
printf "item with index %i in list is 4", firstidx { $_ == 4 } @list;
__END__
item with index 1 in list is 4

Returns -1 if no such item could be found.

first_index is an alias for firstidx.