//e is used for replacement, not matching, so it doesn't seem natural to me. This seems pretty simple: 
my $patt = join '|', @days;
my $days_re = qr/$patt/;

[download]
But if you insist on putting it all on one line, try 
my $days_re = qr/@{ [join '|', @days] }/;

[download]

-Mark

In reply to Re: qr// with /e? by kvale
in thread qr// with /e? by tkil

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