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Message-ID: <4A325980.2000204@ens-lyon.org>
Date: Fri, 12 Jun 2009 15:34:56 +0200
From: Martin Jambon <martin.jambon@ens-lyon.org>
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To: Andrej Bauer <andrej.bauer@andrej.com>
Cc: caml-list@inria.fr
Subject: Re: [Caml-list] ocamllex and python-style indentation
References: <7d8707de0906110557n6a1511a2k9f4f00827f954cb6@mail.gmail.com>	<4A310A5B.9010404@ens-lyon.org> <7d8707de0906120120x10cc8fe0p54adbd189003f3da@mail.gmail.com>
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X-Spam: no; 0.00; ens-lyon:01 ocamllex:01 andrej:01 inserting:01 tokens:01 wrote:01 andreas:01 caml-list:01 jambon:01 jambon:01 indentation:04 nested:04 successive:04 generally:04 depends:04 

Andrej Bauer wrote:
> Thanks to Andreas, I'll have a look at the "old" code.
> 
> I think I understand the general idea of inserting "virtual" tokens,
> but the details confuse me still. So starting with
> 
>> if True:
>>     x = 3
>>     y = (2 +
>>       4 + 5)
>> else:
>>     x = 5
>>     if False:
>>         x = 8
>>         z = 2
> 
> Martin suggests the following:
> 
>> {
>> if True:
>> ;
>>    {
>>    x = 3
>>    ;
>>    y = (2 +
>>    ;
>>      {
>>      4 + 5)
>>      }
>>    }
>> ;
>> else:
>> ;
>>    {
>>    x = 5
>>    ;
>>    if False:
>>    ;
>>        {
>>        x = 8
>>        ;
>>        z = 2
>>        }
>>    }
>> }
> 
> I have two questions. Notice that the { ... } and ( ... ) need not be
> correctly nested (in the top half), so how are we going to deal with
> this?

It depends on the characteristics of your language.
It is generally easier to use several successive passes rather than trying to
do everything in one pass.


Martin

-- 
http://mjambon.com/