If you don't have the more fanciful features of YAML in your input, try YAML::Tiny.

Test.pl

use strict;
use warnings;
use YAML::Tiny;
my $yaml = YAML::Tiny->read('test.yaml');
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Test.yaml

---
rootproperty: blah
section:
  one: two
  three: four
  Foo: Bar
  one: again
  empty: ~
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Results:

D:\>perl test.pl
YAML::Tiny found a duplicate key 'one' in line 'again' at test.pl line
+ 5.
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