diff options
| -rw-r--r-- | perl.html.markdown | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/perl.html.markdown b/perl.html.markdown index 908f300b..a29fdf1f 100644 --- a/perl.html.markdown +++ b/perl.html.markdown @@ -51,6 +51,13 @@ my @mixed = ("camel", 42, 1.23); # indicate one value will be returned. my $second = $animals[1]; +# The size of an array is retrieved by accessing the array in a scalar +# context, such as assigning it to a scalar variable or using the +# "scalar" operator. + +my $num_animals = @animals; +print "Number of numbers: ", scalar(@numbers), "\n"; + ## Hashes # A hash represents a set of key/value pairs: @@ -67,6 +74,11 @@ my %fruit_color = ( # Hash elements are accessed using curly braces, again with the $ sigil. my $color = $fruit_color{apple}; +# All of the keys or values that exist in a hash can be accessed using +# the "keys" and "values" functions. +my @fruits = keys %fruit_color; +my @colors = values %fruit_color; + # Scalars, arrays and hashes are documented more fully in perldata. # (perldoc perldata). @@ -144,6 +156,12 @@ for (@elements) { print; } +# iterating through a hash (for and foreach are equivalent) + +foreach my $key (keys %hash) { + print $key, ': ', $hash{$key}, "\n"; +} + # the Perlish post-condition way again print for @elements; |