[racket-dev] wrong syntax position and span when using unicode lambda character?

Turning on port-count-lines! fixed my problem. Thank you.




On Mon, Jun 11, 2012 at 10:03 PM, Robby Findler
<robby at eecs.northwestern.edu> wrote:
> Yes, sorry for the typo. (The change to line-counting doesn't only add
> line information.)
>
> Robby
>
> On Mon, Jun 11, 2012 at 7:41 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
>> No, Robby meant "on". Line counting matters even more for programs with
>> non-ASCII characters.
>>
>> On Jun 12, 2012, at 8:07 AM, Stephen Chang <stchang at ccs.neu.edu> wrote:
>>
>> Do you mean turn off? I didn't but I will try it. Would it affect some
>> programs but not others though?
>>
>> On Jun 11, 2012 8:01 PM, "Robby Findler" <robby at eecs.northwestern.edu>
>> wrote:
>>>
>>> Did you turn out port-count-lines! on the port?
>>>
>>> Robby
>>>
>>> On Mon, Jun 11, 2012 at 6:57 PM, Stephen Chang <stchang at ccs.neu.edu>
>>> wrote:
>>> > I have a drracket plugin that reads the contents of the definitions
>>> > window as syntax and then traverses that syntax object so that for
>>> > each subexpression e it prints
>>> > 1) (syntax->datum e), and
>>> > 2) the contents of the definitions window at starting at position
>>> > (syntax-position e) and ending at (syntax-position e) + (syntax-span
>>> > e)
>>> >
>>> > I would expect each subexpression in the program to be printed twice
>>> > and the plugin generally works as expected, except when I use the
>>> > unicode lambda character.
>>> >
>>> >
>>> > For example, if I have the program:
>>> >
>>> > #lang racket (add1 10)
>>> >
>>> > the (add1 10) syntax object correctly has position 14 and span 9 and
>>> > the add1 syntax object correctly has position 15 and span 4.
>>> >
>>> >
>>> > But for the program:
>>> >
>>> > #lang racket (λ (x) x)
>>> >
>>> > the (λ (x) x) syntax object has position 14 but span 11 (2 more than
>>> > expected) and the λ syntax object has position 17 (again, 2 more than
>>> > expected)
>>> >
>>> >
>>> > Has anyone seen this behavior before?
>>> >
>>> >
>>> > I'll try to distill my plugin to get something reproducible if it's
>>> > not obvious what's going on.
>>> >
>>> > (I think that syntax positions start at 0 and editor positions start
>>> > at 1 but I account for that so that's not the cause of the problem.)
>>> >
>>> > (I'm also aware that evaluating (syntax-span #'(λ (x) x)) in the repl
>>> > correctly produces 9 so I don't know what's going on.)
>>> >
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>>> >  http://lists.racket-lang.org/dev
>>
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