How to define variables in golang language

How to define variables: 1. Use the var keyword to define one or more variables. The syntax is "var variable name type"; 2. Use the const keyword to define constants. Constants are unmodifiable values, and their values ​​cannot be changed after they are defined. The syntax is "const constant name type = value"; 3. Use type inference to simplify the definition of variables. For example, you can use the := operator to define a variable and have the compiler automatically infer its type. The syntax is "variable name := value"; 4. Define multiple variables at the same time; 5. Blank identifiers, etc.

The operating system for this tutorial: Windows 10 system, go1.20.1 version, Dell G3 computer.

In golang, there are some common ways to define variables, as well as their characteristics and usage.

1. Use the var keyword

In Golang, you can use the var keyword to define one or more variables. The syntax is as follows:

var variable name type

For example, to define an integer variable x:

var x int

This will create a variable named x An integer variable whose initial value is 0. We can also assign an initial value to a variable while defining it, for example:

var y int = 10

This will create an integer variable named y and set its initial value is 10. Of course, we can also use simplified writing:

y := 10

This will automatically infer that the type of y is an integer and set its initial value to 10.

2. Use the const keyword

In Golang, you can use the const keyword to define constants. A constant is an unmodifiable value whose value cannot be changed after it is defined. The syntax is as follows:

const constant name type = value

For example, define a constant pi:

const pi float64 = 3.14159

This will create a name is a constant for pi and sets its value to 3.14159. Unlike variables, constants must be assigned a value when they are defined.

3. Use type inference

In Golang, we can use type inference to simplify the definition of variables. For example, we can use the := operator to define a variable and have the compiler automatically infer its type. The syntax is as follows:

Variable name:= value

For example, define a string variable name and assign its initial value to "John":

name := "John "

At this time, the compiler will automatically infer that the type of name is a string.

4. Multi-variable definition

In Golang, we can define multiple variables at the same time. The syntax is as follows:

var variable name 1, variable name 2, ... variable name n type

For example, define two integer variables a and b:

var a , b int

This will create two integer variables a and b, both with an initial value of 0. We can also assign initial values ​​to multiple variables when defining, for example:

var c, d = 10, 20

This will create two integer variables c and d, and put them The initial values ​​of are set to 10 and 20 respectively. Of course, we can also use type inference to define multiple variables:

e, f := 30, 40

This will create two integer variables e and f, and convert them The initial values ​​of are set to 30 and 40 respectively.

5. Blank Identifier

In Golang, we can use the blank identifier "_" to represent an unwanted value. For example, we can use a whitespace identifier to ignore the value of a variable. For example:

_, err := doSomething()

This will ignore the first return value of the doSomething() function and assign it to the err variable. This is useful when we only care about the error return value of a function.

The above is the detailed content of How to define variables in golang language. For more information, please follow other related articles on the PHP Chinese website!