From: mame@...
Date: 2019-07-30T04:23:28+00:00
Subject: [ruby-core:94021] [Ruby master Bug#10006] instance_exec uses incorrect binding with curried proc

Issue #10006 has been updated by mame (Yusuke Endoh).

Status changed from Open to Rejected

I'm for the first interpretation of @jeremyevans0 .  The semantics is simple and clear.

If `instance_eval` affects the context of curried proc, we need to decide how to handle an intermediate call to `instance_eval` that does not invoke the original proc:

```
f = -> (x, y) { p [x, y, self] }

f1 = f.curry
f2 = "1".instance_exec(1, &f1)
r  = "2".instance_exec(2, &f2) #=> [1, 2, ???]
```

We may respect only the last call to `instance_eval` by ignoring other calls, but it looks more complex than needed.  I prefer the simplicity.

----------------------------------------
Bug #10006: instance_exec uses incorrect binding with curried proc
https://bugs.ruby-lang.org/issues/10006#change-80245

* Author: ledbettj (John Ledbetter)
* Status: Rejected
* Priority: Normal
* Assignee: mame (Yusuke Endoh)
* Target version: 
* ruby -v: ruby 2.2.0dev (2014-07-02 trunk 46660) [x86_64-darwin13]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
After using `Proc#curry`, `instanve_eval`/`instance_exec` does not seem to work:

~~~ruby
class Test
  def test_func
    140
  end
end  # => :test_func

p = ->(x, y) { x + y + test_func }  # => #<Proc:0x007fd23b12bc80@(irb):6 (lambda)>

test = Test.new                     # => #<Test:0x007fd23b0f3d08>
test.instance_exec(1, 2, &p)        # => 143

curried = p.curry[1]                # => #<Proc:0x007fb3142be070 (lambda)>
test.instance_exec(2, &curried)
~~~
~~~
NameError: undefined local variable or method `test_func' for main:Object
	from (irb):6:in `block in irb_binding'
	from (irb):10:in `instance_exec'
	from (irb):10
	from ./bin/irb:11:in `<main>'
~~~



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