Cycle is usually used within a loop to alternate between values, like colors or DOM classes.
{% for item in items %} <div class="{% cycle 'red', 'green', 'blue' %}"> {{ item }} </div> {% end %} <div class="red"> Item one </div> <div class="green"> Item two </div> <div class="blue"> Item three </div> <div class="red"> Item four </div> <div class="green"> Item five</div>
# File lib/liquid/tags/cycle.rb, line 19 def initialize(tag_name, markup, tokens) case markup when NamedSyntax @variables = variables_from_string($2) @name = $1 when SimpleSyntax @variables = variables_from_string(markup) @name = "'#{@variables.to_s}'" else raise SyntaxError.new("Syntax Error in 'cycle' - Valid syntax: cycle [name :] var [, var2, var3 ...]") end super end
# File lib/liquid/tags/cycle.rb, line 33 def render(context) context.registers[:cycle] ||= Hash.new(0) context.stack do key = context[@name] iteration = context.registers[:cycle][key] result = context[@variables[iteration]] iteration += 1 iteration = 0 if iteration >= @variables.size context.registers[:cycle][key] = iteration result end end
# File lib/liquid/tags/cycle.rb, line 49 def variables_from_string(markup) markup.split(',').collect do |var| var =~ /\s*(#{QuotedFragment})\s*/ $1 ? $1 : nil end.compact end