It helps if you spell it right :-) 
$ ./perl6 -e 'supersede sub a { }'
===SORRY!===
"supersede" not yet implemented at line 1, near " sub a { }"

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... for some value of "helps".

What works today is hiding outer sub in an inner lexical scope: 

sub asub ( $ace, $deuce?, $trey? ) {
    say "$ace $deuce $trey";
}

use Test;
plan 1;

{
    sub asub( $ace, $deuce?, $trey? ) { 'asub' };

    is asub(1), 'asub', 'lexically hiding works';
}

[download]
Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re: P6: how to supersede by moritz
in thread P6: how to <strike>supercede</strike> supersede by rir

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