From: Daniel Carrera <dcarrera@...>
Date: 2003-01-23T11:20:44+09:00
Subject: Re: Hash#+ ?

On Thu, Jan 23, 2003 at 11:14:08AM +0900, Tom Sawyer wrote:
> On Wednesday 22 January 2003 06:52 pm, dblack@candle.superlink.net wrote:
> >   No information lost by String#+ or Array#+, but Hash#update may lose
> >   the value.  That's why I rejected the name "+".  It is possible to
> >   provide the non destructive "update" under different name.  Good
> >   name?
> 
> David, what value can be lost? i don't understand.

hash1 = { "key1" => "foo", "key2" => "bar" }
hash2 = { "key1" => "baz", "key3" => "blah" }

hash1 + hash2 # -> What is the value for "key1"?

I like the idea of Hash#| or Hash#or.  It is simply an 'or' function.  
Whichever comes first has precedence:

hash1 | hash2 # -> "key1" => "foo"
hash2 | hash1 # -> "key1" => "baz"

-- 
Daniel Carrera
Graduate Teaching Assistant.  Math Dept.
University of Maryland.  (301) 405-5137