multierror
multierror is a simple Go package for combining multiple errors.
This is handy if you are concurrently running operations within
a function that returns only a single error.
API
multierror exposes two types.
multierror.Errors is a []error with a receiver method Err(),
which returns a multierror.MultiError instance or nil. You use
this type to collect your errors by appending to it.
multierror.MultiError implements the error interface. Its
Errors field contains the multierror.Errors you originally
constructed.
Example
package main
import (
"fmt"
"github.com/joeshaw/multierror"
)
func main() {
// Collect multiple errors together in multierror.Errors
var e1 multierror.Errors
e1 = append(e1, fmt.Errorf("Error 1"))
e1 = append(e1, fmt.Errorf("Error 2"))
// Get a multierror.MultiError from it
err := e1.Err()
// Output: "2 errors: Error 1; Error 2"
fmt.Println(err)
// Iterate over the individual errors
merr := err.(*multierror.MultiError)
for _, err := range merr.Errors {
fmt.Println(err) // Output: "Error 1" and "Error 2"
}
// If multierror.Errors contains no errors, its Err() returns nil
var e2 multierror.Errors
err = e2.Err()
// Output: "<nil>"
fmt.Println(err)
}