86 lines
1.8 KiB
Markdown
86 lines
1.8 KiB
Markdown
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# adverr
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Package adverr implements errors with call stack traces
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as well as error templates for error equality
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## Installation
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```
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go get git.tordarus.net/tordarus/adverr
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```
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## Usage examples
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### Importing
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```go
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import "git.tordarus.net/tordarus/adverr"
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```
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### Creating error templates
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```go
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var (
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ErrDoStuffFailed = adverr.NewErrTmpl("ErrDoStuffFailed", "Could'nt do stuff because of %s")
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)
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```
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### Creating independent error (without error template)
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```go
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func doStuffWithIndependentErr() error {
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return adverr.New("Could'nt do stuff")
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}
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```
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### Creating error based on template
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```go
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func doStuff() error {
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return ErrDoStuffFailed.New("reasons")
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}
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```
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### Printing errors on stderr convieniently
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```go
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adverr.Print(myErr)
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adverr.Println(myErr)
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```
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### Printing errors on stderr and exit with exit code
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```go
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adverr.Fatal(myErr, 1)
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adverr.Fatalln(myErr, 1)
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```
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### Advantages of error templates
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two errors made by the same template will return true when called with `errors.Is()`
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```go
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func doStuffAndFailWithMsg(msg string) error {
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return ErrDoStuffFailed.New(msg)
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}
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err1 := doStuffAndFailWithMsg("err1")
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err2 := doStuffAndFailWithMsg("err2")
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fmt.Println(errors.Is(err1, err2)) // true
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fmt.Println(err1 == err2) // false
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fmt.Println(err1.Error() == err2.Error()) // false
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```
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### Wrapping errors
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By wrapping errors, you can provide an error that is caused by another error.
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A 'Caused by' section will be printed in the stack trace showing the original error.
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You can also retrieve the original error by using `errors.Unwrap()`
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```go
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func doStuffWrapped() error {
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err := doStuff()
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if err != nil {
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return adverr.Wrap("doStuffWrapped failed", err)
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}
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return nil
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}
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```
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### Retrieving call stack trace (for debugging purposes)
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```go
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fmt.Println(adverr.Trace())
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```
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###
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