Method: String#margin

Defined in:
lib/core/facets/string/margin.rb

#margin(num = nil, opts = {}) ⇒ Object

Preserve relative tabbing such that the line with the least amount of white space ends up with the given number of spaces before non-space and all other lines move relative to it.

Because of the nature of this method, leading tab characters (‘t`) must be converted to spaces. The size of a tab can be set via the `:tab` option. The default size is 2.

If the ‘:lead` option is set, then the relative margin is determined by the first non-blank line, instead of the minimum white-space for all lines.

Arguments

num   - The size of the desired margin. [Integer]
opts  - Margin options. [Hash]

Options

:tab  - Size of tab character in spaces. [Integer]
:lead - Use first non-blank line as relative marker. [Boolean]

Returns a new String with adjusted margin. [String]

Author: Gavin Sinclair Author: Trans

Raises:

  • (ArgumentError) 


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# File 'lib/core/facets/string/margin.rb', line 32

def margin(num=nil, opts={})
  # TODO: temporary to help people transition
  raise ArgumentError, "String#margin has been renamed to #trim." unless num

  tab = opts[:tab] || 2
  str = gsub("\t", " " * tab)  # TODO: only leading tabs ?

  if opts[:lead]
    if self =~ /^( *)\S/
      indent(num - $1.length)
    else
      self
    end
  else
    min = []
    str.each_line do |line|
      next if line.strip.empty?
      min << line.index(/\S/)
    end
    min = min.min
    str.indent(num - min)
  end
end