GoDoxy/internal/gperr/README.md

gperr

gperr is an error interface that supports nested structure and subject highlighting.

Usage

gperr.Error

The error interface.

gperr.New

Like errors.New, but returns a gperr.Error.

gperr.Wrap

Like fmt.Errorf("%s: %w", message, err), but returns a gperr.Error.

gperr.Error.Subject

Returns a new error with the subject prepended to the error message. The main subject is highlighted.

err := gperr.New("error message")
err = err.Subject("bar")
err = err.Subject("foo")

Output:

foo > bar: error message

gperr.Error.Subjectf

Like gperr.Error.Subject, but formats the subject with fmt.Sprintf.

gperr.PrependSubject

Prepends the subject to the error message like gperr.Error.Subject.

err := gperr.New("error message")
err = gperr.PrependSubject(err, "foo")
err = gperr.PrependSubject(err, "bar")

Output:

bar > foo: error message

gperr.Error.With

Adds a new error to the error chain.

err := gperr.New("error message")
err = err.With(gperr.New("inner error"))
err = err.With(gperr.New("inner error 2").With(gperr.New("inner inner error")))

Output:

error message:
  • inner error
  • inner error 2
    • inner inner error

gperr.Error.Withf

Like gperr.Error.With, but formats the error with fmt.Errorf.

gperr.Error.Is

Returns true if the error is equal to the given error.

gperr.Builder

A builder for gperr.Error.

builder := gperr.NewBuilder("foo")
builder.Add(gperr.New("error message"))
builder.Addf("error message: %s", "foo")
builder.AddRange(gperr.New("error message 1"), gperr.New("error message 2"))

Output:

foo:
  • error message
  • error message: foo
  • error message 1
  • error message 2

gperr.Builder.Build

Builds a gperr.Error from the builder.

When to return gperr.Error

• When you want to return multiple errors
• When the error has a subject