ruby - undefined function error in rspec -

i having trouble running rspec file, provided part of exercise, , not sure going on.

here code in silly_blocks.rb:

def reverser(num = 1)   result = []   if yield == integer     yield + num   else     yield.split.each{|word| result << word.reverse}     result.join(' ')    end  end 

here rspec file:

require "05_silly_blocks"  describe "some silly block functions"    describe "reverser"     "reverses string returned default block"       result = reverser         "hello"       end       result.should == "olleh"     end      "reverses each word in string returned default block"       result = reverser         "hello dolly"       end       result.should == "olleh yllod"     end   end    describe "adder"     "adds 1 value returned default block"       adder         5       end.should == 6     end      "adds 3 value returned default block"       adder(3)         5       end.should == 8     end   end    describe "repeater"     "executes default block"       block_was_executed = false       repeater         block_was_executed = true       end       block_was_executed.should == true     end      "executes default block 3 times"       n = 0       repeater(3)         n += 1       end       n.should == 3     end      "executes default block 10 times"       n = 0       repeater(10)         n += 1       end       n.should == 10     end    end  end 

i error when hits third test 'adder':

failures:                                                                                                                                      1) silly block functions adder adds 1 value returned default block                                                        failure/error: adder                                                                                                                     nomethoderror:                                                                                                                                undefined method `adder' #<rspec::examplegroups::somesillyblockfunctions::adder:0x007f334345b460>                                     # ./p.rb:30:in `block (3 levels) in <top (required)>'  

it seems adder defined in exact same way previous methods in rspec, not sure going on. have check various other posts haven't found me, or @ least understand enough me.

the function under test (adder) isn't defined yet, spec failure tells. defining part of exercise. define it, add

def adder end 

in 05_silly_blocks.rb, either before or after current code.

(more needed third example pass, got first 2 examples passing, you'll know there.)