ut/README.md

ut package

The ut package exposes some utilities the subpackage utio exposes some IO related utilities. The package is licensed under MIT. Currently this package is still under development and thus the API may break.

API

Packages:

• ut
• utio

ut package

Deopter

Deopter may be used an action may or may not be executed. Particularly useful in combination with defer.

Example:

function Open(p string) (*File, error) {
    var f, _ = os.Open(p)
    var d = NewDeopter(f.Close)
    defer d.Invoke()

    var err error
    // code that might exit early    
    if nil != err {
        return nil, err
    }

    // successful code path
    d.Deopt()
    return f
}

Errors

An Errors struct that represents multiple errors (but still adheres to the error interface)

type Errors struct {
	Errs []error
}

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.

var err error
err = ErrCombine(err, err2)

utio package

Encoder/decoder interfaces and two implementations:

• JSON
• PNG

type Decoder interface {
    Decode(io.Reader) error
}

type Encoder interface {
    Encode(io.Writer) error
}

Utility methods for reading/writing (with or without encoding) files and strings.

// File methods
func DecodeFile(string, Decoder) error
func ReadFile(string, ReadFunc) error

func EncodeFile(string, Encoder) error
func WriteFile(string, WriteFunc) error

// String methods
func DecodeFromString(string, Decoder) error
func ReadFromString(string, ReadFunc) error

func EncodeToString(Encoder) (string, error)
func WriteToString(WriteFunc) (string, error)

Utility methods related to the os/file system.

func Home() (string, error) // returns the user directory
func PathExists(string) bool
func PathDoesNotExist(string) bool