Quick start guide

Open an existing project

• To open a project that you store on your computer, click Open. In the file browser, navigate to a folder with project files and click Open.

  After you have opened your project, you need to specify the location of the Go SDK. You can specify a local path to the SDK or download it. To set the Go SDK, open settings Ctrl+Alt+S and navigate to Go | GOROOT. Click the Add SDK button and select between two options:

  • Local: use a local SDK copy. In the file browser, navigate to the SDK version that is on your hard drive.

  • Download: download the SDK. In the Location field, specify the path for the SDK. To use a file browser, click the Browse icon . Click OK.

  

Clone an existing project from a Version Control System

1. Also, you can download sources from a VCS storage or repository. Click Get from Version Control and select between Git (GitHub) or Mercurial:

   • To check out files from GitHub, click GitHub, enter your credentials and click Log in. Enter a path to the sources and clone the repository to your computer.

   • To check out files from Mercurial, install and configure Mercurial and restart GoLand. Enter a path to the sources and clone the repository to your computer.

2. After you have opened your project, you need to specify the location of the Go SDK. You can specify a local path to the SDK or download it. To set the Go SDK, open settings Ctrl+Alt+S and navigate to Go | GOROOT. Click the Add SDK button and select between two options:

   • Local: use a local SDK copy. In the file browser, navigate to the SDK version that is on your hard drive.

   • Download: download the SDK. In the Location field, specify the path for the SDK. To use a file browser, click the Browse icon . Click OK.

   For more information about version control systems, see Version control.

   

Create a new project

1. To create a project, perform one of the following actions:

   • Select File | New | Project.

   • On the Welcome screen, click New Project.

2. In the New Project dialog, select Go.

   If you plan to work on a project that does not require complex dependency management, consider creating the Go project (File | New | Project). Otherwise, create the Go modules project or enable Go modules in your current project.

3. In the GOROOT field, specify the Go SDK. You can select a local copy of SDK or download it.

   • To select a local copy of the Go SDK, click the Add SDK icon () near the GOROOT field and select Local. In the file browser, navigate to the SDK version that is on your hard drive.

   • To download the Go SDK, click the Add SDK icon () near the GOROOT field and select Download. From the Version list, select the SDK version. In the Location field, specify the path for the SDK. To use a file browser, click the Browse icon . Click OK.

4. Click Create.

   

Create a Go file

1. A new project has no Go files. To create a Go file, perform one of the following actions:

   • Right-click the parent folder of a project, and select New | Go File.

   • Click the parent folder of a project, press Alt+Insert, and select Go File.

   • Click the parent folder of a project, navigate to File | New | Go File.

2. In the New Go File dialog, type a name of the file and select whether you want to create an empty Go file (Empty file) or a Go file with the defined main function (Simple Application).

   

Refactorings

Refactoring is a process of improving your source code without creating a new functionality. Refactoring helps you keep your code solid, dry, and easy to maintain.

GoLand suggests you the following refactoring options:

• Change signature changes the method or function name; adds, removes, and reorders parameters; assigns default values to new non-variadic parameters.

• Extract refactorings extracts code fragments that can be grouped. You can extract a constant, a variable, a method, and an interface.

• Inline refactoring moves an extracted code fragment to the calling code. An opposite to the Extract refactoring.

• Copy refactoring copies a file, a directory, or a package to a different directory or a package.

• Move refactoring moves source code sections to another package or a file. For example, you can use the Move refactoring to move methods to another package.

Code completion

GoLand has two types of code completion:

• Basic code completion Ctrl+Space helps you complete names of types, interfaces, methods, and keywords within the visibility scope. When you invoke code completion, GoLand analyzes the context and suggests the choices that are reachable from the current caret position. By default, GoLand displays the code completion popup automatically as you type.

• Smart code completion Ctrl+Shift+Space filters the suggestions list and shows only the types applicable to the current context.

  The following animation shows the difference between basic and smart type-matching completion. Notice the number of variants that are suggested for different completion types

  

Generating code

GoLand provides multiple ways to generate common code constructs and recurring elements, which helps you increase productivity. These can be either file templates used when creating a new file, custom or predefined live templates that are applied differently based on the context, various wrappers, or automatic pairing of characters.

From the main menu, select Code | Generate Alt+Insert to open the popup menu with available constructs that you can generate.

• You can generate getters, setters, constructors, missing methods, and test files. For more information about the Generate action, see Using the Generate action.

  

Live templates

Use live templates to insert common constructs into your code, such as loops, conditions, various declarations, or print statements.

To expand a code snippet, type the corresponding template abbreviation and press Tab. Keep pressing Tab to jump from one variable in the template to the next one. Press Shift+Tab to move to the previous variable.

• To see the list of live templates, open settings Ctrl+Alt+S and navigate to Editor | Live templates.

  Consider the following example of the Hello World program that is coded with Live Templates.

  

Inspections

In GoLand, there is a set of code inspections that detect and correct anomalous code in your project before you compile it. The IDE can find and highlight various problems, locate dead code, find probable bugs, spelling problems, and improve the overall code structure.

Inspections can scan your code in all project files, or only in specific scopes (for example, only in production code, or in modified files).

Every inspection has a severity level— the extent to which a problem can affect your code. Severities are highlighted differently in the editor so that you can quickly distinguish between critical problems and less important things. GoLand comes with a set of predefined severity levels and enables you to create your own.

• To see the list of inspections, open settings Ctrl+Alt+S and navigate to Editor | Inspections. Disable some of them, or enable others, plus adjust the severity of each inspection. You decide whether it should be considered an error or just a warning.

  For example, the Unreachable code inspection detects parts of code that cannot be executed.

  

Intention actions

As you work in the editor, GoLand analyzes your code, searches for ways to optimize it, and detects potential and actual problems. Intention actions cover a wide range of situations from errors and warnings to optimization suggestions.

In GoLand, you can use the following types of intention actions:

• Intention actions : an action that generates a piece of code or suggests an alternative variant for your code. Usually, an intention action is applied to a valid piece of code. By clicking the yellow bulb icon, you can view intention actions available in the current context. For example, you can create a constructor that generates values of a struct type. Or, replace the if-else statement with the equivalent one but with a negated condition and swapped if-else branches.

• Quick-fixes : an action that suggests a solution for a problem in your code. Usually, the intention action is applied to a code that has an error. For example, when you missed brackets at the end of the expression. Or, when you forgot to convert a value to a specific type.

To see the list of intention actions, open settings Ctrl+Alt+S and navigate to Editor | Intentions.

1. To apply an intention action, click the bulb icon (or press Alt+Enter) to open the list of suggestions.

2. Select an action from the list and press Enter.

   For example, you can use an intention action to inject another language in your code:

   

Run your code

• To run your application Shift+F10, click the Run Application icon and select Run <application_name>.

  

Debug your code

Debugging starts with placing breakpoints at which program execution will be suspended so that you can explore program data. Just click the line in the gutter where you want to place a breakpoint.

• To debug your application Shift+F9, click the Run Application icon and select Debug <application_name>. Then go through the program execution step by step (see the available options in the Run menu or the Debug tool window).

  Refer to the section Debugging for details.