https://github.com/janlelis/multi_block

Pass multiple blocks to a Ruby method
https://github.com/janlelis/multi_block

blocks lambda ruby syntax

Last synced: 1 day ago
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Pass multiple blocks to a Ruby method

• Host: GitHub
• URL: https://github.com/janlelis/multi_block
• Owner: janlelis
• License: mit
• Created: 2015-03-19T20:04:13.000Z (over 9 years ago)
• Default Branch: main
• Last Pushed: 2021-12-29T20:53:09.000Z (almost 3 years ago)
• Last Synced: 2024-05-08T18:19:40.850Z (5 months ago)
• Topics: blocks, lambda, ruby, syntax
• Language: Ruby
• Homepage:
• Size: 19.5 KB
• Stars: 4
• Watchers: 3
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: MIT-LICENSE.txt
  • Code of conduct: CODE_OF_CONDUCT.md

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README

        
# MultiBlock [](https://badge.fury.io/rb/multi_block) [](https://github.com/janlelis/multi_block/actions?query=workflow%3ATest)

MultiBlock is a mini framework for passing multiple blocks to methods. It uses [named procs](https://github.com/janlelis/named_proc) 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