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# FWD: on reading binary operators

• To: larch-interest
• Subject: FWD: on reading binary operators
• From: horning
• Date: Mon, 09 Jan 95 12:14:10 -0800
• Delivery-Date: Mon, 09 Jan 95 12:16:44 -0800

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From: ramshaw@pa.dec.com (Lyle Ramshaw)
Date: Mon, 09 Jan 95 09:18:43 -0800
To: src.theory

Set union and set intersection are generally denoted by binary
operators that are read "cup" and "cap".  Note that "cup" and "cap"
are names for the symbols themselves, while "union" and "intersection"
are the operations that those symbols often denote.

There is another pair of symbols that are used to denote logical
disjunction and conjunction or, more generally, to denote the "join"
and "meet" operations of a lattice.  The TeX names for this pair of
symbols are "vee" and "wedge".  But Andrew M. Gleason told me a
cleverer pair of names, back in the early 70's: "jug" and "jag".
(Webster's Ninth New Collegiate defines "jag" as "a sharp projecting
part: barb".)

If we adopt Gleason's names for that pair of symbols, our next
challenge is to find an analogous pair of names for the symbols that
TeX calls "square-cup" and "square-cap".  I recently asked my sweetie
Kim McGarrity to work on this problem, and she came up with the
following neat pair: "tub" and "tab".  Think of "tab" as -- quoting
from Webster's Ninth once again -- "a projection from a card used as
an aid in filing."

Lyle

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