Go: Stringer Command, Efficiency Through Code Generation

Illustration created for “A Journey With Go”, made from the original Go Gopher, created by Renee French.

ℹ️ This article is based on Go 1.13.

The stringer command aims to automate the creation of methods that satisfy the fmt.Stringer. It generates String() for specified types that describe them as a string.

Case

The documentation of the command provides an example I will use to study the command. Here is the case:

Here is the output:

1

Generating logs with the value of the constants can be a bit confusing.

Let’s generate the String() method with the command stringer -type=Pill:

A new function String() has been generated. Here is the new output when running the previous code:

Aspirin

The type now describes itself as string rather than its inner value.

stringer also works perfectly with the command go generate, making it even more powerful. It is as easy as adding…