Advanced topics

This documentation is for advanced gopls users, who may want to test unreleased versions or try out special features.

Installing unreleased versions

To get a specific version of gopls (for example, to test a prerelease version), run:

GO111MODULE=on go get

Where vX.Y.Z is the desired version.

Unstable versions

To update gopls to the latest unstable version, use:

GO111MODULE=on go get

Working on the Go source distribution

If you are working on the Go project itself, the go command that gopls invokes will have to correspond to the version of the source you are working on. That is, if you have checked out the Go project to $HOME/go, your go command should be the $HOME/go/bin/go executable that you built with make.bash or equivalent.

You can achieve this by adding the right version of go to your PATH (export PATH=$HOME/go/bin:$PATH on Unix systems) or by configuring your editor.

Working with generic code

Gopls has experimental support for generic Go, as defined by the type parameters proposal (golang/go#43651) and type set addendum (golang/go#45346).

To enable this support, you need to build gopls with a version of Go that supports type parameters: the dev.typeparams branch. This can be done by checking out this branch in the Go repository, or by using

$ go get
$ gotip download dev.typeparams

For building gopls with type parameter support, it is recommended that you build gopls at tip. External APIs are under active development on the dev.typeparams branch, so building gopls at tip minimizes the chances of a build failure (though it is still possible). To get enhanced gopls features for generic code, build gopls with the typeparams build constraint (though this increases your chances of a build failure).

$ GO111MODULE=on gotip get -tags=typeparams

This will build a version of gopls that understands generic code. To actually run the generic code you develop, you must also tell the compiler to speak generics using the -G=3 compiler flag. For example

$ gotip run -gcflags=-G=3 .