UNIVER

sub UNIVER {
    [
    <1.1> => 'a',
    <2.0> => 'ẛ',
    <2.1> => '€',
    <3.0> => 'ϟ',
    <3.1> => 'ϴ',
    <3.2> => '⁇',
    <4.0> => 'ȡ',
    <4.1> => 'ℼ',
    <5.0> => 'ↄ',
    <5.1> => 'Ϗ',
    <5.2> => 'Ɒ',
    <6.0> => '✅',
    <6.1> => 'Ɦ',
    <6.2> => '₺',
    <6.3> => 0x061C.chr,
    <7.0> => 0x037F.chr,
    <8.0> => 0x218A.chr,
    <9.0> => 0xA7AE.chr,
    <10.0> => 0x20BF.chr,
    <11.0> => 0xA7AF.chr,
    <12.0> => 0xA7BA.chr,
    <12.1> => 0x32ff.chr,
    <13.0> => 0x1F972.chr,
    <14.0> => 0x061d.chr,
    <15.0> => 0x0cf3.chr,
    ].reverse.first( { .value.uniprop('Age') ne 'Unassigned' } ).key
}

say "Highest supported Unicode version: " ,UNIVER;

# General testing
put "All supported Unicode versions: \n" ,
sort +*, unique (0x20..0x9fff).map({.chr.uniprop(<Age>)}).grep: {so +$_}