From: eregontp@...
Date: 2015-12-02T09:47:21+00:00
Subject: [ruby-core:71801] [Ruby trunk - Feature #11761] `Hash#default_set` and `Hash#default_proc_set`

Issue #11761 has been updated by Benoit Daloze.


Resetting the default value/proc for a Hash multiple times seems a rather special case, could you illustrate why you want to do this?

Hash#merge is not affected by the default values, isn't it?

If it's more like Python setdefault, then I guess (h[k] ||= v).do_sth can work without changing globally the Hash default.

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Feature #11761: `Hash#default_set` and `Hash#default_proc_set`
https://bugs.ruby-lang.org/issues/11761#change-55207

* Author: Tsuyoshi Sawada
* Status: Open
* Priority: Normal
* Assignee: 
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I often want to assign a default value or proc to an existing hash `h` and chain method after it. The way I do it is:

    Hash.new(default_value).merge(h)...
    Hash.new{default_proc_value}.merge(h)...

It would be convenient if I can assign them to a hash directly, and `Hash#default=` and `Hash#default_proc=` are close to doing that, but they are actually not useful because the return value is not the receiver hash:

    h.default = default_value; h...
    h.default_proc = proc {default_proc_value}; h...

I wish there were methods `Hash#default_set` and `Hash#default_proc_set` that return the receiver hash:

    h.default_set(default_value)...
    h.default_proc_set{default_proc_value}...




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