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https://issues.apache.org/jira/browse/CASSANDRA-7740?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14092730#comment-14092730
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Robert Stupp commented on CASSANDRA-7740:
-----------------------------------------

note: in CASSANDRA-7562 I've changed parsing a bit and the end marker is 
{{K_END K_BODY}}

But the main point (anything looking like {{END BODY}} is recognized as the end 
of function body) stays. IMO it was the "lesser of two evils" (compared to 
single-quote-escaping).

I thought about escaping - e.g. {{'}} to {{''}} - but didn't like it. It might 
work for Java - but, as you said, other script languages would look really 
strange.

Something like
{noformat}
CREATE FUNCTION ...
BODY
$function$
    return "END BODY";
$function$
END BODY;
{noformat}
could work - would assume, that {{$function$}} is not used within the body.

Additionally we could also support that {{'}} escaping anyway.
{noformat}
CREATE FUNCTION ...
BODY 
    'return "END BODY";'
END BODY;
{noformat}

I'd personally prefer to implement both ({{$function$...$function$}} and 
string).

Having that, we could also remove the {{K_END K_BODY}} completly and replace 
{{K_BODY}} with {{K_AS}} - have no preference for that.

So this would incorportate two tasks:
* change parsing in cqlsh for {{$function$}}
* change parsing in cqlsh to support multi-line strings
* change parsing in C*


> Parsing of UDF body is broken
> -----------------------------
>
>                 Key: CASSANDRA-7740
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-7740
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Sylvain Lebresne
>            Assignee: Robert Stupp
>
> The parsing of function body introduced by CASSANDRA-7395 is somewhat broken. 
> It blindly parse everything up to {{END_BODY}}, which as 2 problems:
> # it parse function body as if it was part of the CQL syntax, so anything 
> that don't happen to be a valid CQL token won't even parse.
> # something like
> {noformat}
> CREATE FUNCTION foo() RETURNS text LANGUAGE JAVA BODY return "END_BODY"; 
> END_BODY;
> {noformat}
> will not parse correctly.
> I don't think we can accept random syntax like that. A better solution (which 
> is the one Postgresql uses) is to pass the function body as a normal string. 
> And in fact I'd be in favor of reusing Postgresql syntax (because why not), 
> that is to have:
> {noformat}
> CREATE FUNCTION foo() RETURNS text LANGUAGE JAVA AS 'return "END_BODY"';
> {noformat}
> One minor annoyance might be, for certain languages, the necessity to double 
> every quote inside the string. But in a separate ticket we could introduce 
> Postregsql solution of adding an [alternate syntax for string 
> constants|http://www.postgresql.org/docs/9.1/static/sql-syntax-lexical.html#SQL-SYNTAX-DOLLAR-QUOTING].



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