In Go language, calling a structure method requires first defining the structure and the method that binds the receiver, and accessing it using a point number. After defining the structure Rectangle, the method can be declared through the value receiver or the pointer receiver; 1. Use the value receiver such as func(rRectangle)Area()int and directly call it through rect.Area(); 2. If you need to modify the structure, use the pointer receiver such as func(r*Rectangle)SetWidth(...), and Go will automatically handle the conversion of pointers and values; 3. When embedding the structure, the method of embedded structure will be improved, and it can be called directly through the outer structure; 4. Go does not need to force use getter/setter,

Go's time package provides functions for processing time and duration, including obtaining the current time, formatting date, calculating time difference, processing time zone, scheduling and sleeping operations. To get the current time, use time.Now() to get the Time structure, and you can extract specific time information through Year(), Month(), Day() and other methods; use Format("2006-01-0215:04:05") to format the time string; when calculating the time difference, use Sub() or Since() to obtain the Duration object, and then convert it into the corresponding unit through Seconds(), Minutes(), and Hours();

Yes, multiple Go versions can be installed on the same machine. It can be easily implemented using version management tools such as gvm or goenv. Gvm supports package collections, which are suitable for cross-environment testing, while goenv is similar to rbenv and is easy to operate. After installation, version switching is performed through commands such as gvmininstallgo1.20 and gvmusego1.20, and the default version is set. If you do not use the tools, you can manually install different versions to separate directories and switch by modifying the PATH environment variables, such as configuring the shell alias go120 and go121 to quickly switch. Regardless of the method, you should confirm the current version through government and check the Go binary path in the IDE to

InGo,effectiveerrorhandlinguseserrors.Neworfmt.Errorfforbasicerrors,wrapserrorswith%wtopreservecontext,andinspectserrorsusingerrors.Isanderrors.As.1.errors.Newandfmt.Errorfcreatesimpleerrorswithoutcontext.2.Wrappingwith%waddscontextwhilepreservingthe

TogetenvironmentvariablesinGo,useos.Getenv(),butconsiderLookupEnvforexistencechecks.1.Useos.Getenv("VAR_NAME")toretrieveavariable’svalueasastring,returningemptyifunset.2.Useos.LookupEnv()todistinguishbetweenunsetandemptyvariables.3.Provided

The key to installing Go is to select the correct version, configure environment variables, and verify the installation. 1. Go to the official website to download the installation package of the corresponding system. Windows uses .msi files, macOS uses .pkg files, Linux uses .tar.gz files and unzip them to /usr/local directory; 2. Configure environment variables, edit ~/.bashrc or ~/.zshrc in Linux/macOS to add PATH and GOPATH, and Windows set PATH to Go in the system properties; 3. Use the government command to verify the installation, and run the test program hello.go to confirm that the compilation and execution are normal. PATH settings and loops throughout the process

InGo,youcangetthecurrenttimeusingtime.Now(),whichreturnsaTimeobjectrepresentingthelocaltime.Touseit,simplycalltime.Now()andprintorstoretheresult.Forformattedoutput,usetheFormatmethodwithalayoutbasedonthereferencetime"MonJan215:04:05MST2006"

sync.WaitGroup is used to wait for a group of goroutines to complete the task. Its core is to work together through three methods: Add, Done, and Wait. 1.Add(n) Set the number of goroutines to wait; 2.Done() is called at the end of each goroutine, and the count is reduced by one; 3.Wait() blocks the main coroutine until all tasks are completed. When using it, please note: Add should be called outside the goroutine, avoid duplicate Wait, and be sure to ensure that Don is called. It is recommended to use it with defer. It is common in concurrent crawling of web pages, batch data processing and other scenarios, and can effectively control the concurrency process.