From highest to lowest precedence. Default association is "left" (the others are right and non-associate). Left means the LHS is fed into the RHS, right the reverse, and non associative means that the operator can not be repeated.
The L/R column denotes if the Expression is L (left; can be assigned to), R (right; produces a value), or - (not L or R; typically punctuation). This is further explained in L- and R-Value Expressions.
| Operator / Expression | L/R | Association | Explanation |
|---|---|---|---|
; |
- | expression separator, resource body separator | |
| |
- | separator around lambda parameters | |
( |
R | expression grouping () alter precedence of contained expression | |
) |
- | - " - | |
. |
- | inline call operand / function separator | |
CALL |
R | prefixed and inline style calls | |
[ |
R | array start, access operator | |
] |
- | - " - | |
? |
R | select | |
<| <<| |
R | collect (virtual, exported) | |
|> |>> |
- | end of collect (virtual, exported) | |
! |
R | right | not |
- unary |
R | nonassoc | unary minus |
* unary |
R | nonassoc | unary 'splat' for unfolding array |
in |
R | ||
=~ !~ |
R | matches, not-matches | |
* / % |
R | multiplication, division, modulo | |
+ - |
R | addition / concat / merge, subtraction / delete | |
<< >> |
R | left-shift / append, right-shift | |
== != |
R | equal, not-equal | |
> >= < <= |
R | greater, greater-or-equal, less, less-or-equal | |
and |
R | boolean and | |
or |
R | boolean or | |
= |
R | right | assign |
{ |
R | block / hash start | |
{ after ? |
- | block start after ? |
|
} |
- | block / hash / selector end | |
: (in title) |
- | title terminator | |
: (case colon) |
- | case proposition-list terminator | |
=> +> |
- | name-value association | |
, |
- | comma, separator in lists (parameters, arrays, hashes) | |
| L/R-value expression | L/R | Any complete L or R value expression (see expressions) | |
@ @@ |
- | virtual, exported (starts a resource expression) | |
| resource expression | R | resource, resource override, resource default expressions | |
-> ~> <- <~ |
R | relationship | |
| un-parenthesized call | R | statement like calls |
The precedence governs the parsing, not all combinations of expression operator expression are sensical, and those that are not are validated as being in error.
It is of importance to understand the precedence of operators to be able to understand why a particular expression does not give the expected result, or why it produces a particular error message.