class Sass::Tree::ForNode

def to_src(tabs, opts, fmt)

Other tags:
    See: Node#to_src -
def to_src(tabs, opts, fmt)
  to = @exclusive ? "to" : "through"
  "#{'  ' * tabs}@for $#{dasherize(@var, opts)} from #{@from.to_sass(opts)} #{to} #{@to.to_sass(opts)}" +
    children_to_src(tabs, opts, fmt)
end