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

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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