ruby - How to syntactically call a method that takes a block in another method? -

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so i'm new ruby , i'm looking make code little neater , cleaner looking. have these methods in class. made reverse polish notation calculator. know in theory "don't repeat yourself" can see in plus minus divide , times methods do. thing changes +, -, /, *. i'm wondering best way go fixing that? start, here's code. of thoughts below.

class rpncalculator  def initialize     @calculator =  [ ]  end  def push(num)     @calculator << num end  def plus     value = @calculator[-2].to_f + @calculator[-1]     @calculator.delete_at(-2)     @calculator.delete_at(-1)     @calculator << value end  def minus     value = @calculator[-2].to_f - @calculator[-1]     @calculator.delete_at(-2)     @calculator.delete_at(-1)     @calculator << value end  def divide     value = @calculator[-2].to_f / @calculator[-1]     @calculator.delete_at(-2)     @calculator.delete_at(-1)     @calculator << value end   def times     value = @calculator[-2].to_f * @calculator[-1]     @calculator.delete_at(-2)     @calculator.delete_at(-1)     @calculator << value end

basically, i'm thinking make method end_calc() takes block(?). i'm wondering like. example thinking about. 

def end_calc(&block) value = @calculator[-2].to_f &block @calculator[-1]     @calculator.delete_at(-2)     @calculator.delete_at(-1)     @calculator << value end  def plus   end_calc(+) end

basically in methods plus minus etc, call end_calc plus necessary + - / * sign. how can write syntactically + method inserted end_calc? or should go studying in order understand how that? there may more effective not know yet?

you can use following code:

class rpncalculator   def initialize     @calculator = []   end    def push(num)     @calculator << num   end    def plus     do_operation(:+)   end    def minus     do_operation(:-)   end    def divide     do_operation(:/)   end    def times     do_operation(:*)   end    private    def do_operation(operation)     operand_2, operand_1 = @calculator.pop, @calculator.pop     value = operand_1.to_f.send(operation, operand_2)     @calculator << value   end end

also, think should rename times multiply, because method times used repeat block of code several times , may cause misunderstanding.


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