Method: CodeEvents#upon

Defined in:

lib/source/redshift/code_events.rb

#upon(sym_or_hash, unignorable, &block) ⇒ Object

call-seq:

obj.upon(sym, unignorable = false) { |arg,...| block } -> obj
obj.upon(hash)                                         -> obj

Stores a number of Proc objects to be called when the event sym is fired.

The first form adds block to the array of Proc objects executed when the event sym is fired, then returns obj. If unignorable is set to true, the block will be executed when sym fires, regardless of whether it has been ignored.

obj.upon(:A, true) { puts '1st executed' }    #=> obj
obj.upon(:A, true) { puts '2nd executed' }    #=> obj
obj.upon(:A)       { puts '3rd executed' }    #=> obj

obj.ignore(:A)                                #=> obj
obj.fire(:A)                                  #=> obj

produces:

1st executed
2nd executed

The second form takes a hash of Proc objects keyed by event name, running obj.upon(name, &proc) on each key-value pair, then returns obj.

proc_1 = Proc.new { puts '1st executed' }   #=> #<Proc:0x3e78ee>
proc_2 = Proc.new { puts '2nd executed' }   #=> #<Proc:0x3e888a>

obj.upon(:A => proc_1, :B => proc_2)        #=> obj
obj.fire(:B)                                #=> obj

produces

2nd executed

# File 'lib/source/redshift/code_events.rb', line 183

def upon(sym_or_hash, unignorable, &block)
  if sym_or_hash.instance_of?(Hash)
    sym_or_hash.each {|name,proc| self.upon(name, &proc) }
    return self
  else
    name = sym_or_hash.to_sym
    @code_events       ||= {}
    @code_events[name] ||= []
    @code_events[name] << block
    `block.__block__.__unignorable__=typeof(unignorable)=='function'?false:unignorable`
    return self
  end
end