go learn the fifth day, operators

Arithmetic Operators

The following table lists all arithmetic operators Go language. Assuming that A is 10, B is 20

Operators	description	Examples
+	Adding	A + B output 30
-	Subtraction	A - B output -10
*	Multiplied	A * B output 200
/	Divided	B / A output 2
%	Remainder	B% A 0 output
++	Increment	The output 11 A ++
—	Decrement	A- output 9

Go language is no front + + - -
for example: (+ + a, - -a ) this is wrong, not supported

Relational Operators

The following table lists the relational operators Go all languages. Assuming that A is 10, B is 20.

Operators	description	Examples
==	Check the two values are equal, equal returns True if otherwise False.	(A == B) to False
!=	Check the two values are not equal, not equal returns True if otherwise False.	(A! = B) is True
>	Check the left value is greater than the right value, it returns True if it is otherwise False.	(A> B) is False
<	Check the left value is less than the right value, returns True if it is otherwise False.	(A < B) 为 True
>=	Check the left value is greater than or equal to the right value, it returns True if it is otherwise False.	(A> = B) to False
<=	Check the left value is less than or equal to the right value, returns True if it is otherwise False.	(A <= B) 为 True

== compares with an array

The same dimensions and containing the same number of elements the array can compare
Each element of the same are equal

Logical Operators

The following table lists all logical operators in Go. Assuming that A is True, B is False.

Operators	description	Examples
&&	Logical AND operator. If both sides of the operands are True, the conditions are True, otherwise False.	(A && B) 为 False
｜｜	Logical OR operator. If the number of operations on both sides of a True, the conditions are True, otherwise False.	(A \|\| B) is True
!	逻辑 NOT 运算符。如果条件为 True，则逻辑 NOT 条件 False，否则为 True。	!(A && B) 为 True

位运算符

Go 语言支持的位运算符如下表所示。假定 A 为60，B 为13：

运算符	描述	实例
&	按位与运算符”&”是双目运算符。其功能是参与运算的两数各对应的二进位相与。	(A & B) 结果为 12, 二进制为 0000 1100
｜	按位或运算符”	“是双目运算符。其功能是参与运算的两数各对应的二进位相或	(A	B) 结果为 61, 二进制为 0011 1101
^	按位异或运算符”^”是双目运算符。其功能是参与运算的两数各对应的二进位相异或，当两对应的二进位相异时，结果为1。	(A ^ B) 结果为 49, 二进制为 0011 0001
<<	左移运算符”<<”是双目运算符。左移n位就是乘以2的n次方。其功能把”<<”左边的运算数的各二进位全部左移若干位，由”<<”右边的数指定移动的位数，高位丢弃，低位补0。	A << 2 结果为 240 ，二进制为 1111 0000
>>	右移运算符”>>”是双目运算符。右移n位就是除以2的n次方。其功能是把”>>”左边的运算数的各二进位全部右移若干位，”>>”右边的数指定移动的位数。	A >> 2 结果为 15 ，二进制为 0000 1111

&^按位置零

1 &^ 0 -- 1
1 &^ 1 -- 0
0 &^ 1 -- 0
0 &^ 0 -- 0

const (
    Readable  = 1 << iota //0001
    Writable              //0010
    Exectable             //0011
)

func TestBitClear(t *testing.T) {
    a := 7 // 0111
    a = a &^ Readable
    a = a &^ Exectable
    t.Log(a&Readable == Readable, a&Writable == Writable, a&Exectable == Exectable)
}

输出

=== RUN   TestBitClear
--- PASS: TestBitClear (0.00s)
    operator_test.go:25: false true false
PASS

Process finished with exit code 0