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Postings from July 2001
schwern <schwern@pobox.com> wrote: |> On Thu, Jul 19, 2001 at 11:15:12AM -0700, Jeffrey Friedl wrote: |> > I added a new reserved word (I can hear the cringing already) "clamp". |> |> Here's my thoughts about any new attempt to replace pseudo-hashes, My thought of clamp has never been that they are somehow a replacement for pseudo-hashes. They're sort of apples and oranges (although both are orbed fruits). |> sort of a minimal requirement set. |> |> 1) They should act *just like regular hashes* except in that their keyset |> is fixed. I agree. But, I don't think this is relevent to 'clamp'. My idea is that clamp is simple: it makes it an error to add and/or access keys that are not currently there. That's it. It's a new feature for normal hashs. It's very lightweight. Since you can unclamp (or declamp, or whatever) something, it doesn't provide security or anything. Just think of it as a kind of 'use strict' for hash keys: with 'clamp' and some minimal setup, you protect yourself from typos and the like. This is similar to 'use strict' and having to declare your variables. In either cases, the result is wonderful when used appropriately, a nightmare when not. |> clamp() unfortunately violates this. You have to put all your keys in |> the hash before clamping it, so there's effectively no way to |> distinguish between a valid key which has not been set yet and a valid |> key which is set to undef exists() |> clamp() looks to be just as fast as regular hashes. Clamped hashes _are_ regular hashes -- just regular hashes with certain restrictions. The whole point of adding 'clamp' is to be able to add these restrictions. At least that's what I'm thinking...... JeffreyThread Previous | Thread Next