Introduction to Golang and learning of basic grammar

1. What is Golang?

Golang (also known as Go) is a programming language developed by Google. It is a statically typed, compiled, concurrent language designed to build efficient, scalable, and maintainable software systems. Golang has simple syntax, fast compilation speed and good performance, so it is loved and adopted by more and more developers.

2. Install Golang

Before we start using Golang, we need to install the Golang development environment first. Golang supports multiple operating system platforms such as Windows, Mac OS X and Linux. You can choose the corresponding version to install it according to your needs. Here are the installation steps:

OpenGolang official website, download the installation package of the corresponding system. Double-click the installation package to install and follow the prompts to complete the installation process step by step.

After the installation is complete, we can enter it in the command linego versionTo check whether the installation is successful.

3. Write Hello World Programs

After installing Golang, we can try to write the simplest program - Hello World.

Create a name calledThe file is opened using a text editor. Enter the following code:

package main import "fmt" func main() { ("Hello, World!") }

Save the file and enter the directory where the file is located on the command line. Run the program and enter the commandgo run 。

If everything works fine, you should be able to see the output:Hello, World!. Congratulations on successfully writing the first Golang program!

4. Basic grammar

Next, let's learn some basic grammar of Golang:

4.1 Variables

Variables are very important concepts in programs and they are used to store data. In Golang, we can usevarKeyword declaration variables. For example:

var name string = "Alice"

The above code declares a name callednamestring type variable and initialize it to"Alice". We can also omit types and let the compiler automatically infer variable types:

var name = "Alice"

In addition, we can also use:=Operators to simplify variable declaration and initialization:

name := "Alice"

This is equivalent to declaring and initializing a name callednamestring type variable.

4.2 Arrays and slices

An array is a fixed-size, same-type data structure. In Golang, we can define an integer array of length 5 using the following method:

var arr [5]int

Note that the length of the array needs to be specified at creation time and cannot be changed. We can use subscripts to access array elements:

arr[0] = 1 // Set the first element to 1(arr[0]) // Output：1

In addition to arrays, Golang also provides a dynamically sized data structure such as slices. Unlike arrays, the length of the slice can increase or decrease as needed. Here is an example of creating and initializing a slice:

var s []int = make([]int, 5) // Create an integer slice of length 5s[0] = 1 // Set the first element to 1(s[0]) // Output：1

4.3 Control flow

When writing programs, we usually need to perform different operations according to different conditions. In Golang, we can use statements such as if, for and switch to control the program flow.

The if statement is used to perform different operations according to the conditions. Here is a simple if example:

if age &gt;= 18 {
    ("Adults")
} else {
    ("Minor")
}

ifagegreater than or equal to 18, then output"Adults"; otherwise output"Minor"。

The for loop is used to repeatedly execute a specified block of code and can take many forms. Here are the most common forms of for loops:

for i := 0; i < 5; i++ {
    (i)
}

The above code will output numbers from 0 to 4.

The switch statement is used to perform different operations according to different situations. Here is an example:

switch dayOfWeek {
case "Monday":
    ("Monday")
case "Tuesday":
    ("Tuesday")
case "Wednesday":
    ("Wednesday")
default:
    ("other")
}

ifdayOfWeekThe value of"Monday", then output"Monday"; if"Tuesday", then output"Tuesday", and so on. If the value does not match any case, execute the statement in the default code block.

V. Concurrent programming

Golang is a concurrency language that provides a wealth of concurrent programming tools, allowing us to write efficient concurrent programs easily.

There are many ways to implement concurrent programming in Golang, the most commonly used method is to use goroutine and channel. goroutines are lightweight threads managed by the Golang runtime that can perform multiple tasks simultaneously in a program; channels are used to pass data between goroutines.

Here is an example of using goroutine and channel to implement concurrent computing:

func square(num int, out chan<- int) {
    out <- num * num
}
 
func main() {
    numbers := []int{1, 2, 3, 4, 5}
    results := make(chan int)
 
    for _, num := range numbers {
        go square(num, results)
    }
 
    for i := 0; i < len(numbers); i++ {
        (<-results)
    }
}

This code will be correctnumbersEach number in the list is squared and the result is output. usegoThe goroutine with keyword enabled will be executed asynchronouslysquarefunction. The second parameter of the functionoutis a write-only channel used to send the calculation result to the main thread; the main thread passes<-resultsReceive the calculation results and output them.

If you want to study Golang in depth, you can refer to official documents or other related books.

This is the end of this article about the introduction to Golang and learning basic grammar. For more related contents of Golang and basic grammar, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!