# File lib/pry/hooks.rb, line 114 def add_hook(event_name, hook_name, callable=nil, &block) @hooks[event_name] ||= [] # do not allow duplicates, but allow multiple `nil` hooks # (anonymous hooks) if hook_exists?(event_name, hook_name) && !hook_name.nil? raise ArgumentError, "Hook with name '#{hook_name}' already defined!" end if !block && !callable raise ArgumentError, "Must provide a block or callable." end # ensure we only have one anonymous hook @hooks[event_name].delete_if { |h, k| h.nil? } if hook_name.nil? if block @hooks[event_name] << [hook_name, block] elsif callable @hooks[event_name] << [hook_name, callable] end self end