rakudo fails on atomic symbol with a variation

[vrurg]

The Problem

my atomicint $cnt ⚛︎= 0;

This line of code produces a error on macOS. Brief investigation on IRC #perl6 brought up that the atom symbol used above has the following properties:

U+269B ATOM SYMBOL [So]
U+FE0E VARIATION SELECTOR-15 [Mn]

and that everything works find when there is no variation selector.

Expected Behavior

Must pass compilation.

Actual Behavior

This error message is generated:

===SORRY!=== Error while compiling /Users/vrurg/src/Perl/experiments/rakudo/./parallel.p6
Confused
at /Users/vrurg/src/Perl/experiments/rakudo/./parallel.p6:4
------> my atomicint $cnt⏏ ⚛︎= 0;
    expecting any of:
        infix
        infix stopper
        statement end
        statement modifier
        statement modifier loop

Steps to Reproduce

Don't know how to get a symbol with variation on other systems, but on macOS it could be copy-pasted from the character palette.

Environment

• Operating system: macOS 10.13.5
• Compiler version (perl6 -v): This is Rakudo version 2018.06 built on MoarVM version 2018.06

[AlexDaniel]

@samcv @moritz by any chance do you know how to match something like that in a grammar? I think .uniprop(‘Default_Ignorable_Code_Point’) and .uniprop eq ‘Mn’ gives a list of characters that is about right, but then?

For example, :ignoremark ‘⚛’ can match atom symbol with any Extend character, and that's too permissive.

[AlexDaniel]

Please ignore my previous comment. U+FE0E VARIATION SELECTOR-15 [Mn] is special, see https://unicode.org/reports/tr51/#Emoji_Variation_Sequences. So this should work: [‘⚛’|“⚛\xFE0E”].