Cautions and limitations

It is not an implementation similar to CRuby.

The immediate parent of the Delegator class is BasicObject, and customized Kernel objects do not include.
The Delegator instance does not define the method of the delegate object, but it will be called via the method_missing method. This is to save heap memory.
The DelegatorClass method defined in CRuby is undefined.
Some Delegator instance methods defined in CRuby are undefined.

How to install

Build mruby by adding it as a gem to build_config.rb.

MRuby::Build.new do |conf|
  conf.gem "mruby-delegate", github: "dearblue/mruby-delegate"
end

If you want to depend on the mruby gem package, write it in mrbgem.rake.

# mrbgem.rake
MRuby::Gem::Specification.new("mruby-XXX") do |spec|
  ...
  spec.add_dependency "mruby-delegate", github: "dearblue/mruby-delegate"
end

How to use

Maybe it works as https://docs.ruby-lang.org/ja/latest/library/delegate.html ... hopefully.

Specification

Package name: mruby-delegate
Version: 0.2
Product quality: CONCEPT
Author: dearblue
Project page: https://github.com/dearblue/mruby-delegate
Licensing: Creative Commons Zero License (CC0; likely Public Domain)
Required mruby version: 1.4.0 or later
Object code size: 2 Ki bytes on FreeBSD 12.0 AMD64 with clang
Heap usages per one delegate instance (on FreeBSD 12.0 AMD64):
- 48 bytes: delegator object
- 20×N bytes: delegated method table (N is count of string methods (probably more than 160))
- about 3500 bytes: total
Dependency external mrbgems: (NONE)
Bundled C libraries (git-submodules): (NONE)