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- Path: sparky!uunet!charon.amdahl.com!pacbell.com!att-out!rutgers!uwvax!brownie.cs.wisc.edu!so
- From: so@brownie.cs.wisc.edu (Bryan S. So)
- Newsgroups: comp.unix.wizards
- Subject: Re: The Problem with UNIX
- Message-ID: <1992Nov18.022621.24074@cs.wisc.edu>
- Date: 18 Nov 92 02:26:21 GMT
- References: <1992Nov13.094336.2341@aber.ac.uk> <1992Nov13.213107.5722@chpc.utexas.edu> <17934@autodesk.COM>
- Sender: news@cs.wisc.edu (The News)
- Organization: University of Wisconsin, Madison -- Computer Sciences Dept.
- Lines: 56
-
-
- Concerning whether "cat a b > b" should prepend or give warning or does
- whatever it's now doing,
-
- In article <1992Nov13.094336.2341@aber.ac.uk> btk@aber.ac.uk (Ben Ketteridge) writes:
-
- ] Actually, I think this example should work! It is a perfectly
- ] reasonable request.
-
- Another opinion says,
-
- In article <17934@autodesk.COM> dansmith@Autodesk.COM (Daniel Smith) writes:
- )
- ) No it isn't, consider my "glasses of water" theorem:
- >
- )
- ) | | | |
- ) |~~~~~~~~~| |~~~~~~~~~~~|
- ) | | | |
- ) | | | |
- ) | A | | B |
- ) | | | |
- ) \_______/ \_________/
- )
- )
- ) Ok, B can get bigger (i.e. a goblet, or a pitcher) to accept water
- )from A, but what do you mean to do with B's original water? I think
- )B's original water must go to:
- )
- ) | |_
- ) |~~~~~~| \
- ) | C | ||
- ) | |_/
- ) \____/
- )
- ) C, an arbitrary coffee cup in n-dimensional cupboard space, which
- )can expand to hold any amount of liquid found in A & B. I think you're
- )suggesting throwing B's water up in the air while A's water goes to B,
- )and having B's water splash on top. This violates most of the laws of kitchen
- )physics (see Child, Julia "Fractal Baking") and just makes a big mess.
- )The third container (Tupperware or otherwise) saves the day. With
- )this example, you could pour all of the water from C back into B (mv)
- )and then put C in the dishwasher (rm).
-
-
- I would think,
-
- This glasses of water theorem is biased in a sense that Cup C can
- expand to hold any amount of liquid while Cup A and Cup B cannot.
-
- My mental model interpret a file as "n-dimensional cupboard space,
- which can expand to hold any amount of liquid". So, "cat a b > b"
- is reasonable.
-
-
- Bryan
-