ruby block and returning something from block

Question

I am using ruby 1.8.7.

p = lambda { return 10;}
def lab(block)
  puts \'before\'
  puts block.call
  puts \'after\'
end
lab p

Above code output

Answer 1

I think you just need to dereference the block before you pass it:

 foo = lambda { return 10 }

 def trace_block(&fn)
   puts 'before calling fn'
   puts fn.call
   puts 'after caling fn'
 end

 trace_block(&foo)

Output:

  before calling fn
  10
  after caling fn

More info:

• Understanding Ruby Blocks, Procs and Lambdas
• Ruby Blocks 101