Unlike Khen1950fx, I don't expect the syntax for tagged data types to be considered simple. As a matter of fact, YAML::Tiny croaks "YAML::Tiny does not support explicit tags" if you feed them to the module

There might be some bug in YAML::Syck which is preventing your case to work (!var foo), in contrast to (!var [foo]). Because

pirl $> YAML::Syck::Load "--- !!perl/array:var [foo]\n" # long tags
$var = bless( [
                'foo'
              ], 'var' );


pirl $> YAML::Syck::Load "--- !var [foo]\n" # short tags
$var = bless( [
                'foo'
              ], 'var' );
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pirl $> YAML::Syck::Load "--- !!perl/scalar:var foo\n" # long tags, ok
+!
$var = bless( do{\(my $o = 'foo')}, 'var' );


pirl $> YAML::Syck::Load "--- !var foo\n" # short tags, :(
$var = 'foo';
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