chengr4/all-about-Golang

All About Golang

• first-try: This folder includes some try of Golang

• Golang types

• Pointer

• Function

• Logs of learning Golang

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• Go is a pass-by-value language
• In Go, we have convention to put the test file in the same folder with the code (timestamp: 2022)

XXXX_test.go: use test suffix

go test -v -cover ./...

./...: run unit tests in all of tests

Useful Tools

• golang-migrate
• To generate type-safe code from SQL: sqlc

TO READ (new to old):

• 2023.02

Module Management

• go mod init <name with path>: init project
• go build
• go list -m all: 查看 dependency
• go get: add the new dependency
• go mod tidy: 自動刪除未使用的 dependencies

Naming

• https://stackoverflow.com/questions/25161774/what-are-conventions-for-filenames-in-go

Attrbiute

• Strong and statically typed
• Excellent communnity
• Simpicity
• Fast compile times
• Garbage collected: Do not need to focus on manage memory
• built-in testing support
• Object-oriented (but in it's own way)
• Go is a pass by value language
  • Go makes "copies" of values when passed into functions

  See first-try/pass-by-value.go

types

GOTO go types

Non-Pointer Values	Pointer Wrapper Values
string	slice
int	map
float	function
boolean
array
struct

FAQ

1. Why a New Language?

At the moment just before Golang was created:

• Python: Easy to use but slow (interpreted language)
• Java: Increasingly complex type system
• C/C++: Complex type system and Slow compile times (E.g. C++ applications written 10 years age still need to compile today)

How to run a file

go run <name of the file>

What is go.mod

When your code imports packages contained in other modules, you manage those dependencies through your code's own module. That module is defined by a go.mod file that tracks the modules that provide those packages. That go.mod file stays with your code, including in your source code repositor

go mod init example.com/m

Package types

main (executable)

go run *.go
go build -o exec

non main (non executable)

import "github.com/xxxx/xxxxx"

References

1. Learn Go Programming - Golang Tutorial for Beginners (2019.6)
2. The Net Ninja; Go Tutorial (Golang) for Beginners (2021)
3. Standard library
4. Go 14年來的正與負

High Concurrency

1. https://www.ardanlabs.com/blog/2018/08/scheduling-in-go-part1.html?fbclid=IwAR0Qs3jYR4dJBkINCn6BW5lPizwWNPBZRI_8Q6nW27uUdD3M-mdjr3pWKzE

ps. 高效能 backend system 的很好導讀文