Go Language Overview: Features, Concurrency, Types, and Development Tools

Host: Welcome Go

Welcome Go.

1. Reporter: How does Go differ from other languages?

Simplicity, speed, safety

Concurrency, fun, open source

Memory management, array safety, fast compilation

2. Reporter: Where can Go be used?

Web servers, storage clusters, large central servers

Game server development due to massive parallel support

3. Reporter: Tell us about Go's concurrency features.

Goroutine can be started with the go keyword. Goroutine is a lightweight thread managed by the Go runtime.

Syntax:

go functionName(parameterList)

Example:

go f(x, y, z)

Example program demonstrating goroutine execution order:

package main

import ("fmt"; "time")

func say(s string) {
    for i := 0; i < 5; i++ {
        time.Sleep(100 * time.Millisecond)
        fmt.Println(s)
    }
}

func main() {
    go say("test")
    say("hello")
}

Running the program prints “hello” and “test” in nondeterministic order because the two goroutines run concurrently.

4. Reporter: How do goroutines communicate?

Channels

Channels are data structures for passing values between goroutines. The <- operator specifies send or receive direction.

ch <- v    // send v to channel ch
v := <-ch   // receive from ch and assign to v

Declare a channel with make(chan int) . By default channels are unbuffered.

ch := make(chan int)

Example: compute (n² - 5) in two goroutines and sum results.

package main

import "fmt"

func square(s int, c chan int) {
    result := s*s - 5
    c <- result
}

func main() {
    c := make(chan int)
    go square(3, c)
    go square(4, c)
    x, y := <-c, <-c
    fmt.Println(x, y, x+y)
}

Output: 4 11 15

Buffered Channels

Channels can have a buffer size specified in make .

ch := make(chan int, 100)

Buffered channels allow asynchronous send and receive until the buffer is full.

Example of buffered channel:

package main

import "fmt"

func main() {
    ch := make(chan int, 3)
    ch <- 100
    ch <- 200
    ch <- 300
    fmt.Println(<-ch)
    fmt.Println(<-ch)
    fmt.Println(<-ch)
}

Output:

100
200
300

Iterating and Closing Channels

Use range to read from a channel until it is closed.

package main

import "fmt"

func square(n int, c chan int) {
    for i := 1; i <= n; i++ {
        c <- i*i
    }
    close(c)
}

func main() {
    c := make(chan int, 5)
    go square(5, c)
    for i := range c {
        fmt.Println(i)
    }
}

Output:

1
4
9
16
25

Not closing a channel that is no longer used leads to deadlock.

5. Reporter: How to install Go?

Supported OS: Linux, FreeBSD, macOS, Windows

Download from https://golang.org/dl/

Follow the website instructions for installation steps

6. Reporter: What is the basic syntax?

Program consists of tokens: keywords, identifiers, constants, strings, symbols

Each line ends a statement; semicolons are optional

Comments are ignored by the compiler; each package should have a comment

Identifiers are letters, digits, underscores, starting with a letter or underscore

String concatenation uses +

Go has 25 keywords/reserved words

Variable declarations require spaces between tokens

7. Reporter: What data types does Go have?

Boolean: true, false

Numeric: uint8, uint16, uint32, uint64, int8, int16, int32, int64, float32, float64, complex64, complex128

String

Derived types: pointer, array, struct, channel, function, slice, interface, map

8. Reporter: How to declare variables?

Use var keyword

Three forms: explicit type with optional zero value, type inference from initializer, short declaration := (must introduce new variables)

9. Reporter: How to define constants?

Syntax: const identifier [type] = value

Constant types limited to boolean, numeric, and string

10. Reporter: What operators are available?

Arithmetic, relational, logical, bitwise, assignment, others

11. Reporter: What conditional statements exist?

if , if else , switch , select

12. Reporter: What loops are supported?

Only for loop, with break , continue , goto statements.

13. Reporter: How to define functions?

func function_name([parameter list]) [return_types] {
    // function body
}

Explanation of each part follows.

14. Reporter: What are variable scopes?

Local variables: defined inside functions

Global variables: defined outside functions

Formal parameters: variables in function definitions

15. Reporter: How to use arrays?

Declare with element type and size:

var variable_name [SIZE] element_type

Initialize:

var test = [5]float32{200.0, 2.0, 3.14, 20.0, 100.0}

Access via index:

test[4]
test[2] = 100

16. Reporter: How does error handling work?

Go uses the built‑in error interface:

type error interface {
    Error() string
}

Functions return an error value, e.g., using errors.New .

func Sqrt(f float64) (float64, error) {
    if f < 0 {
        return 0, errors.New("math: square root of negative number")
    }
    // implementation
}

17. Reporter: Recommended development tools?

IntelliJ IDEA with Go and File Watcher plugins

GoLand (30‑day free trial)

LiteIDE (open‑source, cross‑platform)

Eclipse

Reference

https://www.runoob.com/go/go-tutorial.html