Class: String

Inherits:
Object
  • Object
show all
Defined in:
lib/active_support/core_ext/string/indent.rb

Instance Method Summary collapse

Instance Method Details

#indent(amount, indent_string = nil, indent_empty_lines = false) ⇒ Object

Indents the lines in the receiver:

"def some_method\n  some_code\nend\n".indent(2)
# =>
  def some_method
    some_code
  end

The second argument, indent_string, specifies which indent string to use. The default is nil, which tells the method to make a guess by peeking at the first indented line, and fallback to a space if there is none.

"  foo".indent(2)        # => "    foo"
"foo\n\t\tbar".indent(2) # => "\t\tfoo\n\t\t\t\tbar"
"foo".indent(2, "\t")    # => "\t\tfoo"

While indent_string is typically one space or tab, it may be any string.

The third argument, indent_empty_lines, is a flag that says whether empty lines should be indented. Default is false.

"foo\n\nbar".indent(2)            # => "  foo\n\n  bar"
"foo\n\nbar".indent(2, nil, true) # => "  foo\n  \n  bar"



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# File 'lib/active_support/core_ext/string/indent.rb', line 40

def indent(amount, indent_string=nil, indent_empty_lines=false)
  dup.tap {|_| _.indent!(amount, indent_string, indent_empty_lines)}
end

#indent!(amount, indent_string = nil, indent_empty_lines = false) ⇒ Object

Same as indent, except it indents the receiver in-place.

Returns the indented string, or nil if there was nothing to indent.



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# File 'lib/active_support/core_ext/string/indent.rb', line 5

def indent!(amount, indent_string=nil, indent_empty_lines=false)
  indent_string = indent_string || self[/^[ \t]/] || ' '
  re = indent_empty_lines ? /^/ : /^(?!$)/
  gsub!(re, indent_string * amount)
end