         "#{@val}#{number}"
     Number.build(value: new_val)
 
+  # @destructive
+  concatenateD: (number)->
+    if @future_as_decimal
+      @val = "#{@val}.#{number}"
+    else
+      @val = "#{@val}#{number}"
+
   futureAsDecimal: ->
     future_as_decimal = !@hasDecimal()
     @clone(future_as_decimal: future_as_decimal)

    expr.push new_last
    @clone(expression: expr)

  replaceLast: (new_last)->
    @withoutLast().append(new_last)



class Exponentiation extends ExpressionComponent
  initialize: (opts={})->
    super
    @baseval = opts.base
    @powerval = opts.power
  isOperator: -> true
