Rules / Operators / multiplicative

+> Skeleton

infix +>

+>
infixmultiplicative 7/27left-assocRaku++ runs this — 1 of 7 results differdocs.raku.org ↗

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 #

Classification #

+> is parsed as an infix at the multiplicative precedence level, left-associative.

That is level 7 of 27 on the ladder, counting from the tightest. Operators sharing a level bind equally; grouping among them is decided by associativity alone.

Shares its precedence level with #

*, /, div, %, %%, mod, +&, +<, ~&, ~<, ~>, ?&, gcd, lcm.

These all bind equally tightly, so an expression mixing them groups by associativity alone.

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.

1 of 7 of these disagree between Raku++ and Rakudo — shown side by side below. A disagreement here is a defect report waiting to be written, not a documented rule.

ExpressionRaku++Rakudo
1 +> 2Int | 0
"a" +> "b"Int | 0ERR Cannot convert string to number: base-10 number must begin with valid digits or '.' in '<HERE>a' (indicated by <HERE>)
1 +> "2"Int | 0
(1, 2) +> (3, 4, 5)Int | 0
True +> FalseInt | 1
Nil +> 1Int | 0
1/2 +> 1/3Rat | 0