Rainer Deyke wrote:
On 11/5/2010 17:41, Walter Bright wrote:
In other words, I create an array that I mean to fill in later, because
I don't have meaningful data for it in advance.
That's a faulty idiom. A data structure that exists but contains no
valid data is a bug waiting to happen - no, it /is/ a bug, even if it
does not yet manifest as incorrect observable behavior. (Or at best,
it's an unsafe optimization technique that should be wrapped up in an
encapsulating function.)
An example would be the bucket array for a hash table. It starts out initially
empty, and values get added to it. I have a hard time agreeing that such a
ubiquitous and useful data structure is a bad idiom.