columnswriter

Documentation

Overview

Package columnswriter imlements a write filter that prints evenly distributed columns fitted to current terminal window size.

Index

• type Writer
  • func New(output io.Writer, inputSep rune, minWidth, padding int) *Writer
  • func (w *Writer) Flush()
  • func (w *Writer) Init(output io.Writer, inputSep rune, minWidth, padding int) *Writer
  • func (w *Writer) Write(buf []byte) (n int, err error)

Examples

• Writer.Flush

Types

type Writer

type Writer struct {
	// contains filtered or unexported fields
}

A Writer is a filter that prints evenly distributed columns

func New

func New(output io.Writer, inputSep rune, minWidth, padding int) *Writer

Create a writer object with specified values, see Init for explanation of paramaters.

func (*Writer) Flush

func (w *Writer) Flush()

Does the actual printing, always call this after everthing you want to print has been printed.

Example

Example of how to call flush after you have written everything

// Print to stdout, input separated by spaces, no min widht, 2 spaces padding
w := New(os.Stdout, ' ', 0, 2)
w.nrTerminalColumns = 80 //for testing purposes, not necessary in real world

fmt.Fprintln(w, `This is a test that has a lot of words and treats every `)
fmt.Fprintln(w, `word as a column.`)
fmt.Fprintln(w, `It should print nicely formatted columns similar to ls `)
fmt.Fprintln(w, `directory lisings on nix systems.`)

w.Flush()

Output:
This     is     a       test       that     has      a   lot      of
words    and    treats  every      word     as       a   column.  It
should   print  nicely  formatted  columns  similar  to  ls       directory
lisings  on     nix     systems.

func (*Writer) Init

func (w *Writer) Init(output io.Writer, inputSep rune, minWidth, padding int) *Writer

A Writer must be initialized with a call to Init. The first pararmater (output) specifies the filter output. The inputSep is the character by wich each field is seperated in the input later on.

minWidth: Is the minimum widht of a column
padding:  The number of spaces between columns

func (*Writer) Write

func (w *Writer) Write(buf []byte) (n int, err error)

Implements Writer interface, so you can call it with the whole Fprint family