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=title Looping over keys of a hash
=timestamp 2012-01-01T01:02:05
=author szabgab
=keywords for, keys
=status show
The same way we can loop over keys of a hash - after
fetching them using the "keys" function.
The declaration of hashes in Perl 6 is similar to that in
Perl 5 but when access individual elements in the hash it
now keeps the % prefix. Thus the value of the key "Foo" will
be %phone{"Foo"}. Similarly if $name contains "Foo" we can
use the %phone{$name} expression to get back the relevant value.
As mentioned earlier the string interpolation of hashes requires
curly braces around the statement.
tutorial/hash/loop_over_hash.p6
#!/usr/bin/env perl6
use v6;
my %phone =
"Foo" => 123,
"Bar" => 456,
;
for keys %phone -> $name {
say "$name %phone{$name}";
}
Output
tutorial/hash/loop_over_hash.p6.out
Bar 456
Foo 123
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