K-user mailing list

[Charles Jacobsen <charlie.jacobsen AT utah.edu>]

krun executes with no error for both the float and integer version. For the 
float version, given the input file:

1.0 + 2.0

the output is

<k>
   3.0
</k>

For the integer version, given the input file:

1 + 2

the output is

<k>
   3
</k>
________________________________________
From: Patrick Meredith 
[pmeredit AT gmail.com]
Sent: Monday, July 08, 2013 10:12 AM
To: Charles Jacobsen
Cc: 
k-user AT cs.uiuc.edu
Subject: Re: [K-user] Using Float literals inside rules

Does the resulting output run correctly?

-Patrick

On Mon, Jul 8, 2013 at 10:55 AM, Charles Jacobsen
<charlie.jacobsen AT utah.edu>
 wrote:
> I might have it set up incorrectly, or I may have misunderstood. This has
> become low priority on my end, so it's really just fyi. When I kompile:
>
> module TEST
>
>    syntax Expr ::= "1.0 + 2.0"
>
>    rule 1.0 + 2.0 => 1.0 +Float 2.0  [structural]
>
> endmodule
>
> I get this:
>
> [Warning] Parser: Parsing ambiguity. Arbitrarily choosing the first.
> 1:
>    1.0 + 2.0 => 1.0 +Float 2.0
> 2:
>    1.0 + 2.0 => 1.0 +Float 2.0
>
> but when I kompile:
>
>
> module TEST
>
>    syntax Expr ::= "1 + 2"
>
>    rule 1 + 2 => 1 +Int 2  [structural]
>
> endmodule
>
> it works with no error.
>
> ________________________________
> From: Radu Mereuta 
> [headness13 AT gmail.com]
> Sent: Thursday, July 04, 2013 6:05 AM
> To: Charles Jacobsen
> Cc: 
> k-user AT cs.uiuc.edu
> Subject: Re: [K-user] Using Float literals inside rules
>
> Hi Charles,
>
> Sorry for the late response.
>
> It can't give ambiguous parsing in those examples, because you didn't define
> the + operator. The only way to parse, is as an Expr, just like you declared
> it.
>
> I think you oversimplified the example, and the issue may be related to
> something that's not present here.
>
> Radu
> K-developer
>
>
> On Wed, Jun 19, 2013 at 10:24 PM, Charles Jacobsen
> <charlie.jacobsen AT utah.edu>
>  wrote:
>>
>> Hello again,
>>
>> This may be a bug, but I am not sure:
>>
>> module TEST
>>
>>    syntax Expr ::= "1.0 + 2.0"
>>
>>    rule 1.0 + 2.0 => 1.0 +Float 2.0  [structural]
>>
>> endmodule
>>
>> leads to a "parsing ambiguity" error, while
>>
>> module TEST
>>
>>    syntax Expr ::= "1 + 2"
>>
>>    rule 1 + 2 => 1 +Int 2  [structural]
>>
>> endmodule
>>
>> does not (and produces 3 when given the program "1+2"). I suspect it's
>> because '.' has special meaning inside k rules. Parsing ambiguity does not
>> result when a Float literal is used inside of the "where" clause of a k
>> rule.
>>
>> _______________________________________________
>> k-user mailing list
>> k-user AT cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/k-user
>>
>



--
-Patrick