   TOKEN_REGEX: /<span class="token" (contenteditable="false" data-id="[0-9]+"|data-id="[0-9]+" contenteditable="false")>[^<]+<\/span>/i
   ID_REGEX: /data-id="[0-9]+"/i
   WORD_REGEX: /[a-z]+$/i
+
+  SUCCESS_COLOR: '#64b80b;'
+  ERROR_COLOR: '#b94a48;'
+  NEUTRAL_COLOR: '#E0E0E0;'
+
+  SUCCESS_MSG: 'Valid equation'
+  ERROR_MSG: 'Syntax error in equation'
+  CHECKING_MSG: 'Checking equation...'
 
   constructor: (@element, @options = {}) ->
     # Remove outline and return if readonly (display) mode.

      @element.addClass "noborder"
      return

    @input = @element.find(".token-text-area-input")

    @input.attr "contenteditable", "true"
    @input.find(".token").attr("contenteditable", "false")

    @element.after('<div style="color: #b94a48; padding-left: 80px; margin-top: 10px; font-size: 12px; line-height: 16px;">Syntax error in formula.</div>')
    @errorMsg = @element.next()
    @errorMsg.hide()

    @typingTimer = null
    @resultMenu = null
    @resultList = null
    @word = null
    @range = null

    @createResultMenu()

    @registerEvents()

  registerEvents: ->

    node.contentEditable = false
    node.dataset.id = id
    node.innerHTML = name
    @range.insertNode(node)

    # Set selection range (i.e. caret position) to new token.
