运算符优先级
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运算符 | 优先级 |
---|---|
postfix | expr++ expr-- |
unary | ++expr --expr +expr -expr ~ ! |
multiplicative | * / % |
additive | + - |
shift | << >> >>> |
relational | < > <= >= instanceof |
equality | == != |
bitwise AND | & |
bitwise exclusive OR | ^ |
bitwise inclusive OR | | |
logical AND | && |
logical OR | || |
ternary | ? : |
assignment | = += -= *= /= %= &= ^= |= <<= >>= >>>= |
Precedence | Operator | Description | Associativity |
---|---|---|---|
1 | :: |
Scope resolution | 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 |
Precedence | Operator | Description | Associativity |
---|---|---|---|
1 | ++ -- |
Suffix/postfix increment and decrement | Left-to-right |
() |
Function call | ||
[] |
Array subscripting | ||
. |
Structure and union member access | ||
−> |
Structure and union member access through pointer | ||
(type){list} |
Compound literal(C99) | ||
2 | ++ -- |
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 | ||
_Alignof |
Alignment requirement(C11) | ||
3 | * / % |
Multiplication, division, and remainder | Left-to-right |
4 | + − |
Addition and subtraction | |
5 | << >> |
Bitwise left shift and right shift | |
6 | < <= |
For relational operators < and ≤ respectively | |
> >= |
For relational operators > and ≥ respectively | ||
7 | == != |
For relational = and ≠ respectively | |
8 | & |
Bitwise AND | |
9 | ^ |
Bitwise XOR (exclusive or) | |
10 | | |
Bitwise OR (inclusive or) | |
11 | && |
Logical AND | |
12 | || |
Logical OR | |
13 | ?: |
Ternary conditional | Right-to-Left |
14 | = |
Simple assignment | |
+= −= |
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 | ||
15 | , |
Comma | Left-to-right |
结合方向 | 运算符 | 附加信息 |
---|---|---|
非结合 | clone new |
clone 和 new |
左 | [ |
array() |
非结合 | ++ -- |
递增/递减运算符 |
非结合 | ~ - (int) (float) (string) (array) (object) (bool) @ |
类型 |
非结合 | instanceof |
类型 |
右结合 | ! |
逻辑操作符 |
左 | * / % |
算术运算符 |
左 | + - . |
算术运算符 和 字符串运算符 |
左 | << >> |
位运算符 |
非结合 | < <= > >= <> |
比较运算符 |
非结合 | == != === !== |
比较运算符 |
左 | & |
位运算符 和 引用 |
左 | ^ |
位运算符 |
左 | | |
位运算符 |
左 | && |
逻辑运算符 |
左 | || |
逻辑运算符 |
左 | ? : |
三元运算符 |
右 | = += -= *= /= .= %= &= |= ^= <<= >>= |
赋值运算符 |
左 | and |
逻辑运算符 |
左 | xor |
逻辑运算符 |
左 | or |
逻辑运算符 |
左 | , |
多处用到 |
这个表给出Python的运算符优先级(从低到高).
从最低的优先级(最松散地结合)到最高的优先级(最紧密地结合)。
这意味着在一个表达式中,Python会首先计算表中较下面的运算符,然后在计算列在表上部的运算符。
运算符 | 描述 |
---|---|
lambda |
Lambda表达式 |
or |
布尔“或” |
and |
布尔“与” |
not x |
布尔“非” |
in,not in |
成员测试 |
is,is not |
同一性测试 |
<,<=,>,>=,!=,== |
比较 |
| |
按位或 |
^ |
按位异或 |
& |
按位与 |
<<,>> |
移位 |
+,- |
加法与减法 |
*,/,% |
乘法、除法与取余 |
+x,-x |
正负号 |
~x |
按位翻转 |
** |
指数 |
x.attribute |
属性参考 |
x[index] |
下标 |
x[index:index] |
寻址段 |
f(arguments...) |
函数调用 |
(experession,...) |
绑定或元组显示 |
[expression,...] |
列表显示 |
{key:datum,...} |
字典显示 |
‘expression,...‘ |
字符串转换 |
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