📅 最后修改于: 2020-11-04 08:57:19 🧑 作者: Mango
运算符定义了将在数据上执行的一些函数。运算符作用的值称为操作数。考虑以下表达式
7 + 5 = 12
此处，值7、5和12是操作数，而+和=是运算符。
榆木的主要运算符可以分类为-
假设变量a和b中的值分别为7和2。
| Sr. No. | Operator | Description | Example |
|---|---|---|---|
| 1 | +(Addition) | returns the sum of the operands | a+b is 9 |
| 2 | -(Subtraction) | returns the difference of the values | a-b is 5 |
| 3 | * (Multiplication) | returns the product of the values | a*b is 14 |
| 4 | / (Float Division) | performs division operation and returns a float quotient | a / b is 3.5 |
| 5 | //(Integer Division) | performs division operation and returns a integer quotient | a // b is 3 |
| 6 | % (Modulus) | performs division operation and returns the remainder | a % b is 1 |
关系运算符测试或定义两个实体之间的关系类型。这些运算符用于比较两个或多个值。关系运算符返回布尔值，即true或false。
假设a的值为10， b的值为20。
| Sr. No. | Operator | Description | Example |
|---|---|---|---|
| 1 | > | Greater than | (a > b) is False |
| 2 | < | Lesser than | (a < b) is True |
| 3 | >= | Greater than or equal to | (a >= b) is False |
| 4 | <= | Lesser than or equal to | (a <= b) is True |
| 5 | == | Equality | (a == b) is false |
| 6 | != | Not equal | (a != b) is True |
运算符(例如> =或<)可用于可比较类型。这些定义为数字，字符，字符串和列表，元组。运算符两侧的可比较类型必须相同。
| Sr. No. | Comparable Type | Example |
|---|---|---|
| 1 | number | 7>2 gives True |
| 2 | character | ‘a’ ==’b’ gives False |
| 3 | string | “hello” ==”hello” gives True |
| 4 | tuple | (1,”One”)==(1,”One”) gives True |
| 5 | list | [1,2]==[1,2] gives True |
打开榆树REPL并尝试下面显示的示例-
C:\Users\admin>elm repl
---- elm-repl 0.18.0 -----------------------------------------------------------
:help for help, :exit to exit, more at
--------------------------------------------------------------------------------
> 7>2
True : Bool
> 7.0>2
True : Bool
> 7.0<2.0
False : Bool
> 'a' > 'b'
False : Bool
> 'a' < 'b'
True : Bool
> "a" < "b"
True : Bool
> (1,2) > (2,3)
False : Bool
> ['1','3'] < ['2','1']
True : Bool
>
逻辑运算符用于组合两个或多个条件。逻辑运算符也返回布尔值。
| Sr. No. | Operator | Description | Example |
|---|---|---|---|
| 1 | && | The operator returns true only if all the expressions specified return true | (10>5) && (20>5) returns True |
| 2 | || | The operator returns true if at least one of the expressions specified return true | (10 < 5) || (20 >5) returns True |
| 3 | not | The operator returns the inverse of the expression’s result. For E.g.: !(>5) returns false. | not (10 < 5) returns True |
| 4 | xor | The operator returns true only if exactly one input returns true. The operator returns false if both the expressions return true. | xor (10 > 5 ) (20 > 5) returns false |