[ruby/irb] Refactor exit command

(https://github.com/ruby/irb/pull/835)

* Remove unnecessary code from the exit command's implementation

1. The parameters of `IRB.irb_exit` were never used. But there are some
   libraries seem to call it with arguments + it's declared on the top-level
   IRB constant. So I changed the params to anonymous splat instead of removing them.
2. `Context#exit` was completely unnecessary as `IRB.irb_exit` doesn't use
   the `@irb` instance it passes. And since it's (or should be treated as)
   a private method, I simply removed it.
3. The `exit` command doesn't use the status argument it receives at all.
   But to avoid raising errors on usages like `exit 1`, I changed the argument to
   anonymous splat instead removing it.

* Make exit an actual command

* Update readme

https://github.com/ruby/irb/commit/452b543a65

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/irb.rb b/lib/irb.rb
index daa0d64f28..4de8dda071 100644
--- a/lib/irb.rb
+++ b/lib/irb.rb
@@ -886,8 +886,8 @@ module IRB
   end
 
   # Quits irb
-  def IRB.irb_exit(irb, ret)
-    throw :IRB_EXIT, ret
+  def IRB.irb_exit(*)
+    throw :IRB_EXIT
   end
 
   # Aborts then interrupts irb.