Columnize - Format an Array as a Column-aligned String

In showing a long lists, sometimes one would prefer to see the value
arranged aligned in columns. Some examples include listing methods of
an object, listing debugger commands, or showing a numeric array with data
aligned.

Setup

$ irb
>> require ‘columnize’
=> true

With numeric data

>> a = (1..10).to_a
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

>> a.columnize
=> “1 2 3 4 5 6 7 8 9 10”

>> puts a.columnize :arrange_array => true, :displaywidth => 10
[1, 2, 3,
4, 5, 6,
7, 8, 9,
10]
=> nil

>> puts a.columnize :arrange_array => true, :displaywidth => 20
[1, 2, 3, 4, 5, 6,
7, 8, 9, 10]
=> nil

With String data

>> g = %w(bibrons golden madascar leopard mourning suras tokay)
=> [“bibrons”, “golden”, “madascar”, “leopard”, “mourning”, “suras”, “tokay”]

>> puts g.columnize :displaywidth => 15
bibrons suras
golden tokay
madascar
leopard
mourning
=> nil

>> puts g.columnize :displaywidth => 19, :colsep => ‘ | ’
bibrons | suras
golden | tokay
madascar
leopard
mourning
=> nil

>> puts g.columnize :displaywidth => 18, :colsep => ‘ | ’, :ljust => false
bibrons | mourning
golden | suras
madascar | tokay
leopard
=> nil

Using Columnize.columnize

>> Columnize.columnize(a)
=> “1 2 3 4 5 6 7 8 9 10”

>> puts Columnize.columnize(a, :displaywidth => 10)
1 5 9
2 6 10
3 7
4 8
=> nil

>> Columnize.columnize(g)
=> “bibrons golden madascar leopard mourning suras tokay”

>> puts Columnize.columnize(g, :displaywidth => 19, :colsep => ‘ | ’)
bibrons | mourning
golden | suras
madascar | tokay
leopard
=> nil

Credits

This is adapted from a method of the same name from Python’s cmd module.

Other stuff

Authors: Rocky Bernstein and Martin Davis

Warranty

You can redistribute it and/or modify it under either the terms of the GPL
version 2 or the conditions listed in COPYING

Modules

Classes