From: oinkoink+unet@... (Bret Jolly)
Date: 2002-11-15T09:01:26+09:00
Subject: Syntactic Sugar Question

Ruby has the nifty syntactic sugar by which

foo ||= "oink"

will set foo to "oink" if foo is uninitialized (or nil or false), but will
leave foo alone otherwise.  I like this, but how the heck does it work?
This is evidently syntax sugar for

foo = (foo || "oink")

which works the same way.  But if foo is uninitialized, the expression

foo || "oink"

gives an error message like
NameError: undefined local variable or method `foo' for #<Object:0x401e5ce0>

To add to the mystery,

foo ||= false unless not foo

sets foo to nil (not to false)!  I'm a confused piggy.
Regards, Bret
http://www.rexx.com/~oinkoink