! Skeleton
infix !
!The rules for ! have not been written yet. Everything below is extracted rather than authored: the official documentation supplies the classification, and the interpreters were asked directly about the rest.
What is established #
What the interpreter said #
Raku++ parses this spelling. Asked to compile:
my $a = 6; my $b = 3; sink($a !== $b)
…it got through the parser. On its own that establishes very little: it says nothing about whether the construct executes, let alone whether the result is right. Where the behaviour table below exists, that is the stronger evidence — those expressions were actually run.
Covered upstream #
The official documentation has a section for this construct: docs.raku.org. Until the rules here are written, that is the better reference.
Observed behaviour #
Each expression below was executed by both interpreters when this page was built; the results are recorded, not written. The operands are chosen to cross the boundaries that catch people out: string against number, a list where a scalar was meant, a boolean, an undefined value, and an exact rational.
Raku++ and Rakudo agree on every row below.
| Expression | Raku++ | Rakudo |
|---|---|---|
1 ! 2 | rejected by both — Parse error | |
"a" ! "b" | rejected by both — Parse error | |
1 ! "2" | rejected by both — Parse error | |
(1, 2) ! (3, 4, 5) | rejected by both — Parse error | |
True ! False | rejected by both — Parse error | |
Nil ! 1 | rejected by both — No such method 'Nil' for invocant of type 'Bool' | |
1/2 ! 1/3 | rejected by both — Parse error | |