C Operator Precedence Reference

Source: ISO/IEC 9899:2011 (C11), §6.5 and Annex A.
Used as reference for the Pratt parser binding-power table in src/parser/precedence.rs.

Full C Precedence Table (highest → lowest)

Level Operators Description Associativity
15 () [] . -> ++ -- (postfix) Postfix / member access Left → Right
14 ++ -- (prefix) + - (unary) ! ~ * (deref) & (addrof) sizeof (type) cast Prefix unary / cast Right → Left
13 * / % Multiplicative Left → Right
12 + - Additive Left → Right
11 << >> Bitwise shift Left → Right
10 < <= > >= Relational Left → Right
9 == != Equality Left → Right
8 & Bitwise AND Left → Right
7 ^ Bitwise XOR Left → Right
6 \| Bitwise OR Left → Right
5 && Logical AND Left → Right
4 \|\| Logical OR Left → Right
3 ?: Ternary conditional Right → Left
2 = += -= *= /= %= &= ^= \|= <<= >>= Assignment Right → Left
1 , Comma Left → Right

Mapping to Pratt binding powers

In a Pratt parser, lbp (left binding power) determines when the operator fires; rbp (right binding power) is passed as min_bp to the recursive right-side parse.

Currently implemented operators

Operator(s) lbp rbp Associativity C level
= += -= *= /= %= &= ^= \|= <<= >>= 1 1 Right 2
?: 2 2 Right 3
\|\| 4 5 Left 4
&& 6 7 Left 5
\| 8 9 Left 6
^ 10 11 Left 7
& 12 13 Left 8
== != 14 15 Left 9
< <= > >= 16 17 Left 10
<< >> 18 19 Left 11
+ - 20 21 Left 12
* / % 22 23 Left 13
prefix unary / cast — 30 Right 14
postfix ++ -- [] () . -> > 30 — Left 15

Operators not yet implemented

Operator(s) C level Notes
, 1 Comma operator (below assignment)