Re: PSQL commands: \quit_if, \quit_unless

On 12/2/16 9:24 AM, Robert Haas wrote:
> On Fri, Dec 2, 2016 at 11:12 AM, Corey Huinker <corey.huinker@gmail.com> wrote:
>> In order for me to understand how high the bar has been set, can you
>> (Robert/Tom mostly, but I welcome any responses) explain what you mean by
>> "full-blown expression language"? What constructs must it include, etc?
>
> I mostly mean it should be based on flex and bison, not "this is so
> simple I can just hand-roll it".  I don't think it has much chance of
> staying that simple.

It might be worth looking at other simplistic languages for guidance. 
bash comes to mind, though there's GPL issues there. csh/tcsh don't have 
those problems, and perhaps some of their grammar could be stolen.

I find it interesting that this is kind of the opposite problem that 
most pl's face: how to fit the database access paradigm into the 
language with the minimal amount of extra effort for users.

http://cvsweb.netbsd.org/bsdweb.cgi/src/bin/csh/?only_with_tag=MAIN
https://github.com/tcsh-org/tcsh
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