[perl #125580] [BUG] bag/set related issues

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# <URL: https://rt.perl.org/Ticket/Display.html?id=125580 >


15:20 < kanl> my $a = bag( -Inf .. Inf ); my $b = bag( 1 .. 3 ); my $c = bag();
              say $a(+)$b(+)$c; ## this won't work
15:21 < kanl> 1. Inf is not properly guarded
15:21 < kanl> 2. the (whatever) operator requires leading whitespaces.
15:21 < kanl> 3. can't mix the operators without grouping ()
15:23 < kanl> m: my $a = bag( 1 .. 4 ); my $b = bag( 1 .. 3 ); say $a(+)$b;
15:23 < kanl> m: my $a = bag( 1 .. 4 ); my $b = bag( 1 .. 3 ); my $c = bag();
              say $a (+) $b (-) $c;
15:23 <+camelia> rakudo-moar 377672: OUTPUT«===SORRY!=== Error while compiling
                 /tmp/hlD7eRLLzW␤Prefix + requires an argument, but no valid
                 term found␤at /tmp/hlD7eRLLzW:1␤------>  .. 4 ); my $b = bag(
                 1 .. 3 ); say $a(+⏏)$b;␤    expecting any of:␤        prefix␤»
15:24 <+camelia> rakudo-moar 377672: OUTPUT«===SORRY!=== Error while compiling
                 /tmp/YpB9DyyE64␤Operators '(+)' and '(-)' are non-associative
                 and require parentheses␤at /tmp/YpB9DyyE64:1␤------> ( 1 .. 3
                 ); my $c = bag(); say $a (+) $b⏏ (-) $c;␤    expecting any
                 of:␤        i…»