From @masak

<TimToady> nr​: $_ = "foo bar"; say m/ $( $_ ) /
<p6eval> niecza v22-13-g0d2a99e​: OUTPUT«#<match from(0) to(7) text(foo
bar) pos([].list) named({}.hash)>␤»
<p6eval> ..rakudo 7731d2​: OUTPUT«#<failed match>␤»
<TimToady> nr​: my $x = "foo bar"; $_ = $x; say m/ $( $x ) /
<p6eval> niecza v22-13-g0d2a99e​: OUTPUT«#<match from(0) to(7) text(foo
bar) pos([].list) named({}.hash)>␤»
<p6eval> ..rakudo 90fad9​: OUTPUT«#<failed match>␤»
<TimToady> that one seems like an unrelated bug
<TimToady> probably not parsing $() as a variable there
<masak> nod
* masak submits rakudobug
<TimToady> nr​: my $x = "foo bar"; $_ = $x; say m/ $( 1 2 ) /
<p6eval> niecza v22-13-g0d2a99e​: OUTPUT«===SORRY!===␤␤Unable to parse
argument list [...]
<p6eval> ..rakudo 90fad9​: OUTPUT«#<failed match>␤»
<TimToady> yes, it thinks it's just $ and () separately

From @FROGGS

Fix​:
Raku/nqp@b8a381e

Test​:
Raku/roast@5a4c6b7

The RT System itself - Status changed from 'new' to 'open'

@FROGGS - Status changed from 'open' to 'resolved'