Module: Strings::Align

Defined in:
lib/strings/align.rb

Overview

Responsible for text alignment

Constant Summary collapse

NEWLINE = 
"\n"
SPACE = 
" "
LINE_BREAK = 
%r{\r\n|\r|\n}.freeze

Class Method Summary collapse

Class Method Details

.align(text, width, direction: :left, **options) ⇒ Object

Aligns text within the width.

If the text is greater than the width then unmodified string is returned.

Examples:

text = "the madness of men"

Strings::Align.align(text, 22, direction: :left)
# => "the madness of men      "

Strings::Align.align(text, 22, direction: :center)
# => "   the madness of men   "

Strings::Align(text, 22, direction: :right)
# => "      the madness of men"

Strings::Align.align(text, 22, direction: :center, fill: "*")
# => "***the madness of men***"

Parameters:

  • text (String) —

    the text to align lines of

  • width (Integer) —

    the maximum width to align to



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# File 'lib/strings/align.rb', line 39

def align(text, width, direction: :left, **options)
  return text if width.nil?

  method = to_alignment(direction)
  send(method, text, width, **options)
end

.align_center(text, width, fill: SPACE, separator: nil) ⇒ String

Centers text within the width

Returns:

  • (String) 


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# File 'lib/strings/align.rb', line 86

def align_center(text, width, fill: SPACE, separator: nil)
  return text if width.nil?
  sep = separator || text[LINE_BREAK] || NEWLINE

  each_line(text, sep) do |line|
    width_diff = width - display_width(line)
    if width_diff > 0
      right_count = (width_diff.to_f / 2).ceil
      left_count  =  width_diff - right_count
      [fill * left_count, line, fill * right_count].join
    else
      line
    end
  end
end

.align_left(text, width, fill: SPACE, separator: nil) ⇒ String

Aligns text to the left at given length

Returns:

  • (String) 


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# File 'lib/strings/align.rb', line 66

def align_left(text, width, fill: SPACE, separator: nil)
  return if width.nil?
  sep = separator || text[LINE_BREAK] || NEWLINE

  each_line(text, sep) do |line|
    width_diff = width - display_width(line)
    if width_diff > 0
      line + fill * width_diff
    else
      line
    end
  end
end

.align_right(text, width, fill: SPACE, separator: nil) ⇒ String

Aligns text to the right at given length

Returns:

  • (String) 


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# File 'lib/strings/align.rb', line 108

def align_right(text, width, fill: SPACE, separator: nil)
  return text if width.nil?
  sep = separator || text[LINE_BREAK] || NEWLINE

  each_line(text, sep) do |line|
    width_diff = width - display_width(line)
    if width_diff > 0
      fill * width_diff + line
    else
      line
    end
  end
end

.display_width(string) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Visible width of a string



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# File 'lib/strings/align.rb', line 142

def display_width(string)
  Unicode::DisplayWidth.of(Strings::ANSI.sanitize(string))
end

.each_line(text, separator) ⇒ String

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Enumerate text line by line

Parameters:

  • text (String)

Returns:

  • (String) 


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# File 'lib/strings/align.rb', line 130

def each_line(text, separator)
  lines = text.split(separator)
  return yield(text) if text.empty?
  lines.reduce([]) do |aligned, line|
    aligned << yield(line)
  end.join(separator)
end

.to_alignment(direction) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Convert direction to method name



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# File 'lib/strings/align.rb', line 50

def to_alignment(direction)
  case direction.to_sym
  when :left   then :align_left
  when :right  then :align_right
  when :center then :align_center
  else
    raise ArgumentError, "Unknown alignment `#{direction}`."
  end
end