94 lines
1.9 KiB
Markdown
94 lines
1.9 KiB
Markdown
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# ut package
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The ut package exposes some utilities the subpackage [utio](utio) exposes some IO related utilities. The package is licensed under [MIT](LICENSE). Currently this package is still under development and thus the API may break.
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## API
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Packages:
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- [ut](#ut-package)
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- [utio](#utio-package)
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### ut package
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**Deopter**
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`Deopter` may be used an action may or may not be executed. Particularly useful in combination with defer.
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Example:
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```
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function Open(p string) (*File, error) {
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var f, _ = os.Open(p)
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var d = NewDeopter(f.Close)
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defer d.Invoke()
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var err error
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// code that might exit early
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if nil != err {
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return nil, err
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}
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// successful code path
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d.Deopt()
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return f
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}
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```
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**Errors**
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An `Errors` interface that represents multiple errors (but still adheres to the `error` interface)
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```
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type Errors interface {
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error
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Errs() []error
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}
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```
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Combine errors using `ErrCombine` when you want to combine multiple errors as one. Makes use of the `Errors` interface when there is more than one error.
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```
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var err error
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err = ErrCombine(err, err2)
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```
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### utio package
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Encoder/decoder interfaces and two implementations:
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- JSON
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- PNG
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```
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type Decoder interface {
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Decode(io.Reader) error
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}
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type Encoder interface {
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Encode(io.Writer) error
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}
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```
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Utility methods for reading/writing (with or without encoding) files and strings.
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```
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// File methods
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func DecodeFile(string, Decoder) error
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func ReadFile(string, ReadFunc) error
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func EncodeFile(string, Encoder) error
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func WriteFile(string, WriteFunc) error
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// String methods
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func DecodeFromString(string, Decoder) error
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func ReadFromString(string, ReadFunc) error
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func EncodeToString(Encoder) (string, error)
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func WriteToString(WriteFunc) (string, error)
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```
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Utility methods related to the os/file system.
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```
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func Home() (string, error) // returns the user directory
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func PathExists(string) bool
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func PathDoesNotExist(string) bool
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```
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