Re: do your bit for my mental health - how to find the difference between two strings?

On 16 Dec 2010, at 18:17, Brian Candler wrote:

> Iain Barnett wrote in post #968894:
>>>   service =3D params[:service]
>>>   service.replace('servicename')    # <<<<
>>>   STDERR.puts service.inspect, service.encoding
>>>   mymethod( service )
>>>=20
>>> Try running this with the marked line present, and with that line
>>> commented out.
>>=20
>> this bore some info. I'm running Ruby 1.92 (sorry, I should have
>> mentioned that) with Sinatra 1.1.0. With the replace function the
>> encoding is US-ASCII, or UTF-8 if I set the `# encoding: utf-8` at =
the
>> top of the file.
>>=20
>> Without the replace function the encoding is ASCII-8BIT. I've been
>> searching around for how to make all this work now I know this, and
>> poking around in the Sinatra and Rack source, but haven't found a
>> (working) answer yet. I'll post it when I do.
>=20
> OK, well you should now be able replicate this without Sinatra:
>=20
> foo =3D "servicename"
> foo.force_encoding("ASCII-8BIT")
> mymethod(foo)
>=20
> Note that Sinatra gives you a parameter tagged as ASCII-8BIT, more or=20=

> less by accident (i.e. it's not documented as far as I know); it's=20
> simply that Ruby defaults to ASCII-8BIT when reading data from a =
socket,=20
> as opposed to from a file.
>=20
> If you really want the gorey details, I attempted to document about =
200=20
> ruby 1.9 string behaviours at=20
> https://github.com/candlerb/string19/blob/master/string19.rb
>=20
> Anyway, you can now investigate what's going on in mymethod() which=20
> might be affected by the encoding. If you are using sqlite3 inside =
that=20
> method, you may have hit upon the bug already discovered at
> http://www.ruby-forum.com/topic/476119
>=20
> If you don't want to understand what's going on, you can do
> service.force_encoding("UTF-8")
> and cross your fingers. It might fix the problem, or it might be =
hiding=20
> some other more serious problem which will explode on you at some=20
> indeterminate time in the future.
>=20
> But as far as I'm concerned, this is all total crap. I stick with ruby=20=

> 1.8 for exactly this reason.
>=20
> --=20
> Posted via http://www.ruby-forum.com/.

Yep, I am using Sqlite3 so I tried the force_encoding just after I =
replied and bingo! You're right. I'm going to look into Rack Request and =
Response and perhaps patch them to enforce it there, but for now I'm a =
lot happier. It is a stupid bug, but I like the lambda syntax in 1.9 so =
I'm not giving it up :)

I'll take a look at the string behaviours too, thanks for the link.

Regards,
Iain=