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Date: Wed, 01 Aug 2007 09:24:33 +0200
From: Georg Bauhaus <bauhaus.rm.tsoh@maps.futureapps.de>
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Subject: Re: Unary operator after binary operator: legal or not? => Compiler
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Date: 2007-08-01T09:20:25+02:00
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Robert A Duff wrote:

> 
> But what's the general principle?

My guess is,  "logical and relational operators were separated
from other binary operators to get reasonable precedence behavior",
as per Jeff Carter. And likely an architect would not want
to build on top of chains of punctuation symbols condensing
meaning into character sequences that look more like molecules
rather than text.

IIRC, ML and APL have no overloadings of '-' for negation
and subtration. Will users still see a readability problem
once there are more satisfactory solutions of the two cases:

 -X

and

 +"Y"

Or perhaps Robert Dewar's suggestion to reserve one punctuation
symbol not currently in the language for user defined operator
overloading might help, like "$"? Or, since $ is used in some
preprocessors, one symbol that is wisely picked from the set
of symbols available in ISO 10646. Just one.