Re: Adding a distinct "pattern" type to resolve the "~" commutator stalemate

On 06/19/2011 02:56 PM, Robert Haas wrote:
> On Sun, Jun 19, 2011 at 9:53 AM, Florian Pflug<fgp@phlo.org>  wrote:
>> Amidst the discussion, Alvaro suggested that we resolve the issue
>> by adding a distinct type for patterns as opposed to text. That'd
>> allow us to make "~" it's own commutator by defining both
>>   text ~ pattern
>> and
>>   pattern ~ text.
> That's kind of a neat idea.  There might be an efficiency benefit to
> having a regex type that is precompiled by the input function.


What do we do when we get text or unknown in place of pattern? How are 
we going to know if the pattern is supposed to be the left or right operand?

cheers

andrew