In perl.git, the branch blead has been updated
<http://perl5.git.perl.org/perl.git/commitdiff/f94762723eddc4a0de865db28c07e020aecf8d06?hp=12916dad38433a42694da808e8ec9eafc149f1c8>
- Log -----------------------------------------------------------------
commit f94762723eddc4a0de865db28c07e020aecf8d06
Author: Alexander Hartmaier <abra...@cpan.org>
Date: Fri Feb 11 15:36:21 2011 +0100
perldoc improvements for map
M pod/perlfunc.pod
commit 14cca8c3de3e3a27586eea0be45a1e045981c98d
Author: Father Chrysostomos <spr...@cpan.org>
Date: Sun Feb 13 11:39:58 2011 -0800
Add Alexander Hartmaier to AUTHORS
M AUTHORS
-----------------------------------------------------------------------
Summary of changes:
AUTHORS | 1 +
pod/perlfunc.pod | 21 +++++++++++++++++++--
2 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/AUTHORS b/AUTHORS
index 93b7a13..deef7d1 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -40,6 +40,7 @@ Albert Chin-A-Young <ch...@thewrittenword.com>
Albert Dvornik <b...@alum.mit.edu>
Alessandro Forghieri <a...@orion.it>
Alexander Alekseev <a...@alemate.ru>
+Alexander Hartmaier <abra...@cpan.org>
Alexei Alexandrov <alexei.alexand...@gmail.com>
Alex Davies <adav...@ptc.com>
Alex Gough <a...@rcon.org>
diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod
index ece1005..d85b3d7 100644
--- a/pod/perlfunc.pod
+++ b/pod/perlfunc.pod
@@ -2996,9 +2996,26 @@ total number of elements so generated. Evaluates BLOCK
or EXPR in
list context, so each element of LIST may produce zero, one, or
more elements in the returned value.
- @chars = map(chr, @nums);
+ @chars = map(chr, @numbers);
-translates a list of numbers to the corresponding characters. And
+translates a list of numbers to the corresponding characters.
+
+ my @squares = map { $_ * $_ } @numbers;
+
+translates a list of numbers to their squared values.
+
+ my @squares = map { $_ > 5 ? ($_ * $_) : () } @numbers;
+
+shows that number of returned elements can differ from the number of
+input elements. To omit an element, return an empty list ().
+This could also be achieved by writing
+
+ my @squares = map { $_ * $_ } grep { $_ > 5 } @numbers;
+
+which makes the intention more clear.
+
+Map always returns a list which can be assigned to a hash where the elements
+become key/value pairs. See L<perldata> for more details.
%hash = map { get_a_key_for($_) => $_ } @array;
--
Perl5 Master Repository
