أسبقية تنفيذ المعاملات
الجدول التالي يحتوي على معاملات في C++ مرتبة من الأعلى إلى الأسفل حسب الأولوية .
| الأسبقية | العامل | الشرح | الترابط |
|---|---|---|---|
| 1 | :: | المدى الحالي . | Left-to-right |
| 2 | ++-- | Suffix/postfix increment and decrement | |
() | Function call | ||
[] | Array subscripting | ||
. | Element selection by reference | ||
−> | Element selection through pointer | ||
| 3 | ++-- | Prefix increment and decrement | Right-to-left |
+− | Unary plus and minus | ||
!~ | Logical NOT and bitwise NOT | ||
(type) | Type cast | ||
* | Indirection (dereference) | ||
& | Address-of | ||
sizeof | Size-of | ||
new, new[] | Dynamic memory allocation | ||
delete, delete[] | Dynamic memory deallocation | ||
| 4 | .*->* | Pointer to member | Left-to-right |
| 5 | */% | Multiplication, division, and remainder | |
| 6 | +− | Addition and subtraction | |
| 7 | <<>> | Bitwise left shift and right shift | |
| 8 | <<= | For relational operators < and ≤ respectively | |
>>= | For relational operators > and ≥ respectively | ||
| 9 | ==!= | For relational = and ≠ respectively | |
| 10 | & | Bitwise AND | |
| 11 | ^ | Bitwise XOR (exclusive or) | |
| 12 | | | Bitwise OR (inclusive or) | |
| 13 | && | Logical AND | |
| 14 | || | Logical OR | |
| 15 | ?: | Ternary conditional | Right-to-Left |
| 16 | = | Direct assignment (provided by default for C++ classes) | |
+=−= | Assignment by sum and difference | ||
*=/=%= | Assignment by product, quotient, and remainder | ||
<<=>>= | Assignment by bitwise left shift and right shift | ||
&=^=|= | Assignment by bitwise AND, XOR, and OR | ||
| 17 | throw | Throw operator (for exceptions) | |
| 18 | , | Comma | Left-to-right |
When parsing an expression, an operator which is listed on some row will be bound tighter (as if by parentheses) to its arguments than any operator that is listed on a row further below it. For example, the expressions std::cout<<a&b and *p++ are parsed as (std::cout<<a)&b and *(p++), and not as std::cout<<(a&b) or (*p)++.
Operators that are in the same cell (there may be several rows of operators listed in a cell) are evaluated with the same precedence, in the given direction. For example, the expression a=b=c is parsed as a=(b=c), and not as (a=b)=c because of right-to-left associativity.
An operator's precedence is unaffected by overloading.
[تعديل]Notes
The standard itself doesn't specify precedence levels. They are derived from the grammar.
const_cast, static_cast, dynamic_cast, reinterpret_cast and typeid are not included since they are never ambiguous.
Some of the operators have alternate spellings (e.g., and for &&, or for ||, not for !, etc.).
[تعديل]See also
Order of evaluation of operator arguments at run time.
| Common operators | ||||||
|---|---|---|---|---|---|---|
| assignment | increment decrement | arithmetic | logical | comparison | member access | other |
a = b | ++a | +a | !a | a == b | a[b] | a(...) |
| Special operators | ||||||
static_cast converts one type to another compatible type | ||||||
