Re: [9fans] awk help; not plan9 matter

[Rudolf Sykora <rudolf.sykora@gmail.com>]

forget about my previous post regarding the leading space,
I am tired, it was wrong...

Anyway the question about () is still hot...
R

2009/9/17 Rudolf Sykora <rudolf.sykora@gmail.com>:
> 2009/9/17 erik quanstrom <quanstro@quanstro.net>:
>> i don't think you need an extra () for the leading
>> white space.  just tack it on in with the leading expression.
>
> see below
>
>> the hoc is unnecessary.  just start with 2.
> true :)
>
>> fn buildre {
>>        re = 's:^([     ]*'
>>        for(i in `{seq 2 $1})
>>                re = $re ^ '[^  ]+[     ]+'
>>        re = $re ^ ')([^        ]+):\1' ^ $2:
>> }
>>
>> ; buildre 1 hell
>> ; whatis re
>> re='s:^([       ]*)([^  ]+):\1hell:'
>
> already here is a problem:
> 1) I am to save the leading space --- so it shouldn't be an argument to s.
> 2) only the 2nd () --- the word with no spaces in itself --- is to be changed
> ... since the spaces are to be preserved, none of them should be an
> argument to the s command, I think. That's why it was treated
> seperately by me.
>
> Anyway, what do you think about that problem with the empty group? Why
> linux is ok with it while plan 9 is not? Is there any reason? Is that
> a bug in plan9 sed?
>
> Thanks
> Ruda
>
>> ; buildre 2 hell
>> ; whatis re
>> re='s:^([       ]*[^    ]+[     ]+)([^  ]+):\1hell:'
>>
>> - erik
>>
>>
>