Class: String

Inherits:
Object show all
Defined in:
lib/core_ext/object/blank.rb,
lib/core_ext/string/truncate.rb

Constant Summary collapse

BLANK_RE =

rails may be loaded by client

/\A[[:space:]]*\z/.freeze

Instance Method Summary collapse

Instance Method Details

#blank? ⇒ true, false

A string is blank if it’s empty or contains whitespaces only:

''.blank?       # => true
'   '.blank?    # => true
"\t\n\r".blank? # => true
' blah '.blank? # => false

Unicode whitespace is supported:

"\u00a0".blank? # => true

Returns:

  • (true, false) 


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# File 'lib/core_ext/object/blank.rb', line 115

def blank?
  # The regexp that matches blank strings is expensive. For the case of empty
  # strings we can speed up this method (~3.5x) with an empty? call. The
  # penalty for the rest of strings is marginal.
  empty? || BLANK_RE === self
end

#truncate(maximum_length, omission: '…', mode: :right) ⇒ Object 



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# File 'lib/core_ext/string/truncate.rb', line 2

def truncate(maximum_length, omission: '…', mode: :right)
  case mode
  when :right, 'right'
    truncate_right(maximum_length, omission: omission)
  when :middle, 'middle'
    truncate_middle(maximum_length, omission)
  else
    raise ArgumentError, "Unsupported mode (#{mode}), expected [:middle, :right]."
  end
end

#truncate_middle(maximum_length = 3, separator = '…') ⇒ Object

Truncates the middle, leaving portions from start & end see stackoverflow.com/a/62713671



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# File 'lib/core_ext/string/truncate.rb', line 30

def truncate_middle(maximum_length = 3, separator = '…')
  return '' if maximum_length.zero?
  return self if length <= maximum_length

  middle_length = length - maximum_length + separator.length
  edges_length = (length - middle_length) / 2.0
  left_length = edges_length.ceil
  right_length = edges_length.floor

  left_string = left_length.zero? ? '' : self[0, left_length]
  right_string = right_length.zero? ? '' : self[-right_length, right_length]

  "#{left_string}#{separator}#{right_string}"
end

#truncate_right(truncate_at, options = {}) ⇒ Object

File activesupport/lib/active_support/core_ext/string/filters.rb, line 66



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# File 'lib/core_ext/string/truncate.rb', line 14

def truncate_right(truncate_at, options = {})
  return dup unless length > truncate_at

  omission = options[:omission] || '…'
  length_with_room_for_omission = truncate_at - omission.length
  stop = if options[:separator]
           rindex(options[:separator], length_with_room_for_omission) || length_with_room_for_omission
         else
           length_with_room_for_omission
    end

  +"#{self[0, stop]}#{omission}"
end