Feature #4234: Hash#default_proc= Doesn't Accept nil Argument

• Status: Closed
• Assignee: marcandre (Marc-Andre Lafortune)
• Target version: -

[runpaint (Run Paint Run Run)]

=begin
The initial value of a Hash's default Proc is the block passed to Hash.new or nil. Hash#default_proc= can set the default Proc to a given Proc, but can't reset it to nil. This is unsymmetrical.

The attached patch lets #default_proc= take a nil argument, and provides tests. This causes a RubySpec failure ("Hash#default_proc= raises an error if passed stuff not convertible to procs"), which I will fix if this patch is applied.
=end

[naruse (Yui NARUSE)]

• Status changed from Open to Assigned
• Assignee set to akr (Akira Tanaka)

[marcandre (Marc-Andre Lafortune)]

• Tracker changed from Bug to Feature
• Assignee changed from akr (Akira Tanaka) to matz (Yukihiro Matsumoto)
• Priority changed from 3 to Normal

Changing this to 'feature'.

I'm in favor of this change, with a small change to the doc. The interface should be read:

hsh.default_proc = proc_obj or nil

I think it is indeed not clear how to clear a default_proc. See:
http://stackoverflow.com/questions/3818623/marshal-ruby-hash-with-default-proc-remove-the-default-proc

Thoughts?

[matz (Yukihiro Matsumoto)]

• Assignee changed from matz (Yukihiro Matsumoto) to marcandre (Marc-Andre Lafortune)

Agreed. Marc, could you check this patch in (with document update)?

Matz.

[marcandre (Marc-Andre Lafortune)]

• Status changed from Assigned to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r35268.
Run Paint, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

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• hash.c (rb_hash_set_default_proc): Accept nil, patch by Run Paint
  [Feature #4234]

• test/ruby/test_hash.rb: test for above.