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- Subject: undef [was: Re: metatable transmission]
- From: spir <denis.spir@...>
- Date: Tue, 22 Dec 2009 20:25:04 +0100
Mark Hamburg <email@example.com> dixit:
Same for me. In // worlds ;-) there are loads of discussions about semantic overloading of null/nil/none, which cause difficult to understand/debug issues.
I long for a "non-settable" (*) value meaning undefined, and only that, that can safely be used with a semantics similar to #ifdef.
x = undef --> error
return undef --> error
so we cannot charge "undef" with undue semantic meaning (eg "special case", "not found", "exception", "to-be-provided-later"). These are roles for "nil", or better for user-defined or builtin flag values.
la vita e estrany