Indentation

DESCRIPTION:

A small library of extensions to Ruby’s Array and String classes that allow indentation manipulation of Strings and Arrays of Strings. Has the capability of working with multi-line strings. If you frequently use String arrays to manipulate text, see synopsis (In README.rdoc) for examples of how indentation can make your life easier.

EXAMPLES:

Indent

# Default indentation is 2 spaces
  "test".indent # => "  test"

# Amount of indentation can be changed
  "test".indent(3) # => "   test"

# Indentation character (or string) is set as the second parameter of indent.
  "test".indent(2, "\t") # => "\t\ttest"

# Operates on multi-line strings
  "this\nis\na\ntest".indent # => "  this\n  is\n  a\n  test"

# Indent method accepts negative values (Removes tabs, spaces, and supplied indentation string)
  "  test".indent(-1) # => " test"
  "\t test".indent(-5) # => "test"
  "\t--     Test".indent(-10) # => "--     Test"
  "\t--     Test".indent(-10, '-') # => "Test"
  "--- Test".indent(-2, '--') # => "- Test"

# Operates on arrays
  ["one", "two"].indent # => ["  one", "  two"]
  [["one", "  two"], ["uno", "\t\tdos"]].indent # => [["  one", "    two"], ["  uno", "  \t\tdos"]]

Reset Indentation

# 'resets' the indentation of a string by finding the least amount of indentation in the String/Array, and
# removing that amount from every line.
  "  def method_name\n    # Do stuff\n  end".reset_indentation # => "def method_name\n  # Do stuff\nend"

# Operates on arrays
  ["  def method_name", "    # Do stuff", "  end"].reset_indentation # => ["def method_name", "  # Do stuff", "end"]

# Useful for heredocs - must chomp to remove trailing newline
  my_string = <<-EOS.chomp.reset_indentation
    def method_name
      # Do stuff
    end
    EOS
  my_string # => "def method_name\n  # Do stuff\nend"

# Accepts an indentation modifier
  " one\n  two".reset_indentation(1) # => " one\n  two"
  "   one\n  two".reset_indentation(0) # => " one\ntwo" # Default behavior
  " one\n  two".reset_indentation(-1) # => "one\ntwo"

Append Separator

# Given an Array of Arrays or an Array of Strings, appends a separator object to all but the last element in the Array.
# NOTE: For an Array of Strings the separator object must be a String, since it is appended to other Strings
  ["arg1", "arg2", "arg3"].append_separator("!") # => ["arg1!", "arg2!", "arg3"]
  [["line1"], ["line2"], ["line3"]].append_separator("") # => [["line1", ""], ["line2", ""], ["line3"]]
  [["line1", "line2"], ["line3", "line4"]].append_separator("") # => [["line1", "line2", ""], ["line3", "line4"]]

# Useful combined with indent and join
  vars = ["var1", "var2", "var3", "var4"]
  method_def = ["def add_up(#{vars.join(', ')})"]
  method_body = vars.append_separator(" + ")
  method_def += method_body.indent
  method_def << "end"
  method_def.join("\n") # =>
    # def add_up(var1, var2, var3, var4)
    #   var1 + 
    #   var2 + 
    #   var3 + 
    #   var4
    # end

# Handy for separating arrays of string arrays
  test_array = [["this", "is", "a", "test"], ["quick", "brown", "fox"], ["lazy", "typist"]]
  test_array.append_separator("").join("\n") # =>
    # this
    # is
    # a
    # test
    # 
    # quick
    # brown
    # fox
    # 
    # lazy
    # typist

Find Least Indentation

# Given a String or Array of Strings, finds the least indentation on any line. Splits on newlines found within strings
# to find the least indentation within a multi-line String
"  test".find_least_indentation # => 2
"   three\n  two \n one".find_least_indentation # => 1
["  two", "   three", "    four"].find_least_indentation # => 2
["  two", "   three", ["    four", "     five\n one"]].find_least_indentation # => 1

# Option to ignore blank (no characters whatsoever) lines. 
# Note, disabling this option will automatically disable :ignore_empty_lines
# Default => true
  "   three\n".find_least_indentation # => 3
  "   three\n".find_least_indentation(:ignore_blank_lines => false) # => 0

# Option to ignore both blank lines (no characters whatsoever) and empty lines (whitespace-only)
# Implies :ignore_blank_lines => true when enabled
# Default => true
  "   three\n ".find_least_indentation # => 3
  "   three\n ".find_least_indentation(:ignore_empty_lines => false) # => 1
  "   three\n".find_least_indentation # => 3
  "   three\n".find_least_indentation(:ignore_empty_lines => false) # => 0

# To ignore blank, but not empty, lines:
  "   three\n ".find_least_indentation(:ignore_blank_lines => true, :ignore_empty_lines => false) # => 1
  "   three\n".find_least_indentation(:ignore_blank_lines => true, :ignore_empty_lines => false) # => 3

English Array Join

# Given an Array of Strings and an optional conjunction, joins them using English list punctuation
# to find the least indentation within a multi-line String
['one', 'two'].english_join # => "one and two"
['one', 'two', 'three'].english_join # => "one, two, and three"

# Different conjunction
['one', 'two', 'three'].english_join('or') # => "one, two, or three"

# Different separator
['one', 'two', 'three'].english_join('or', ' ') # => "one two or three"

REQUIREMENTS:

  • none

INSTALL:

  • sudo

    gem install indentation

    • (Use sudo unless using rvm)

LICENSE:

(The MIT License)

Copyright © 2010 Prometheus Computing

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.