MultiBlock 
MultiBlock is a mini framework for passing multiple blocks to methods. It uses named procs to accomplish this with a simple syntax. The receiving method can either yield all blocks, or just call specific ones, identified by order or name.
Currently supports CRuby only.
Setup
Add to Gemfile:
gem 'multi_block'
Usage
Defining methods that use multiple blocks
The first argument given to yield always defines the desired block(s). The other arguments get directly passed to the block(s):
yield # calls all given procs without args
yield :success # calls :success proc without args
yield :success, "Code Brawl!" # calls :success proc with message
yield 1 # calls first proc (:success in this case)
yield [:success, :bonus] # calls :success and :bonus without args
yield [:success, :bonus], "Code Brawl!" # calls both procs with same arg
yield success: "Code Brawl!", # calls each keyed proc,
error: [500, "Internal Brawl Error"] # values are the args
Calling methods with multiple blocks
Consider these two example methods:
# calls the :success block if everything worked well
def ajax
yield rand(6) != 0 ? :success : :error
end
# calls the n-th block
def dice
random_number = rand(6)
yield random_number, random_number + 1
end
Multiple blocks can be passed using blocks:
ajax &blocks[
proc.success{ puts "Yeah!" },
proc.error { puts "Error..." },
]
The dice method could, for example, be called in this way:
dice &blocks[
proc{ ":(" },
proc{ ":/" },
proc{ ":O" },
proc{ ":b" },
proc{ ":P" },
proc{ rand(42) != 0 ? ":)" : ":D"},
]
Bonus sugar: Array extension
If you like the slim &to_proc operator, you can further optimize the syntax by activating the core extension for array:
require 'multi_block/array'
Now you do not need the blocks helper anymore. Instead just do:
do_something, some_argument, &[
proc.easy_way{
# do it the easy way
},
proc.complex_way{
# use complex heuristics, etc.
},
]
MIT License
See the original gist: https://gist.github.com/4b2f5fd0b45118e46d0f