[ruby-core:72989] [Ruby trunk - Feature #10320] require into module

Issue #10320 has been updated by J旦rg W Mittag.


Nobuyoshi Nakada wrote:
> I think this feature should be an instance method of `Module`, similar to `load` rather than `require`.

Yes, I believe having `Module#load` and possibly `Module#require` and `Module#require_relative` would be the most logical:

~~~ruby
# not namespaced:
require 'foo'
module Bar;end

# namespaced:
module Bar
  require 'foo'
end
~~~

Re-using those names would be a backwards-incompatible change, though. I have seen people use the second form sometimes.

This is a replacement for the hard-to-use `wrap` optional argument to `Kernel#load`:

~~~ruby
load 'foo', true

# is almost equivalent to 

Module.new.load 'foo'
~~~

This can be naturally extended to `Binding#load`, `Binding#require`, and `Binding#require_relative`.

As with the `wrap` argument to `Kernel#load`, the question is, what should references like `::String` in the loaded script refer to? I think it would be nice if it offered *complete* isolation by default, with an option to revert to the current behavior of `load`, e.g. with an API like this:

~~~ruby
class Module
  def load(path, pollute_global: false)
  end
end
~~~

----------------------------------------
Feature #10320: require into module
https://bugs.ruby-lang.org/issues/10320#change-56209

* Author: So Wieso
* Status: Open
* Priority: Normal
* Assignee: 
----------------------------------------
When requiring a library, global namespace always gets polluted, at least with one module name. So when requiring a gem with many dependencies, at least one constant enters global namespace per dependency, which can easily get out of hand (especially when gems are not enclosed in a module).

Would it be possible to extend require (and load, require_relative) to put all content into a custom module and not into global namespace?

Syntax ideas:

~~~ruby
require 'libfile', into: :Lib   # keyword-argument
require 'libfile' in Lib   # with keyword, also defining a module Lib at current binding (unless defined? Lib)
require_qualified 'libfile', :Lib
~~~

This would also make including code into libraries much easier, as it is well scoped.

~~~ruby
module MyGem
  require 'needed' in Need

  def do_something
    Need::important.process!
  end
end
 # library user is never concerned over needed's content
~~~

Some problems to discuss:

* requiring into two different modules means loading the file twice?
* monkeypatching libraries should only affect the module ­→ auto refinements?
* maybe also allow a binding as argument, not only a module?
* privately require, so that required constants and methods are not accessible from the outside of a module (seems to difficult)
* what about $global constants, read them from global scope but copy-write them only to local scope?

Similar issue:
https://bugs.ruby-lang.org/issues/5643



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