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parse error on input when print specified lines of a file

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  parse error on input when print specified lines of a file meInvent bbird <jobmattcon@gmail.com> - 2016-08-23 01:52 -0700
    Re: parse error on input when print specified lines of a file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-23 11:00 +0100
      Re: parse error on input when print specified lines of a file meInvent bbird <jobmattcon@gmail.com> - 2016-08-23 18:40 -0700
        Re: parse error on input when print specified lines of a file meInvent bbird <jobmattcon@gmail.com> - 2016-08-23 18:49 -0700
        Re: parse error on input when print specified lines of a file Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-08-24 10:07 +0100

#455 — parse error on input when print specified lines of a file

parse error on input `\'

import System.IO  
import Control.Monad

main = do
  file <- readFile "hello.txt"
  forM_ [5..7] (lines file) \i -> 
      putStrLn i 

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#456

meInvent bbird <jobmattcon@gmail.com> writes:

> parse error on input `\'
>
> import System.IO  
> import Control.Monad
>
> main = do
>   file <- readFile "hello.txt"
>   forM_ [5..7] (lines file) \i -> 
>       putStrLn i

Did you mean

  forM_ (lines file) (\i -> putStrLn i)

?  The syntax error is that you need ()s round the lambda expression
here, but the extra list [5..7] is puzzling me.

-- 
Ben.

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#457

would like to choose specified lines to display

On Tuesday, August 23, 2016 at 6:00:07 PM UTC+8, Ben Bacarisse wrote:
> meInvent bbird <jobmattcon@gmail.com> writes:
> 
> > parse error on input `\'
> >
> > import System.IO  
> > import Control.Monad
> >
> > main = do
> >   file <- readFile "hello.txt"
> >   forM_ [5..7] (lines file) \i -> 
> >       putStrLn i
> 
> Did you mean
> 
>   forM_ (lines file) (\i -> putStrLn i)
> 
> ?  The syntax error is that you need ()s round the lambda expression
> here, but the extra list [5..7] is puzzling me.
> 
> -- 
> Ben.

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#458

line number 5 to line number 7

On Wednesday, August 24, 2016 at 9:40:55 AM UTC+8, meInvent bbird wrote:
> would like to choose specified lines to display
> 
> On Tuesday, August 23, 2016 at 6:00:07 PM UTC+8, Ben Bacarisse wrote:
> > meInvent bbird <jobmattcon@gmail.com> writes:
> > 
> > > parse error on input `\'
> > >
> > > import System.IO  
> > > import Control.Monad
> > >
> > > main = do
> > >   file <- readFile "hello.txt"
> > >   forM_ [5..7] (lines file) \i -> 
> > >       putStrLn i
> > 
> > Did you mean
> > 
> >   forM_ (lines file) (\i -> putStrLn i)
> > 
> > ?  The syntax error is that you need ()s round the lambda expression
> > here, but the extra list [5..7] is puzzling me.
> > 
> > -- 
> > Ben.

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#459

meInvent bbird <jobmattcon@gmail.com> writes:
>
> On Tuesday, August 23, 2016 at 6:00:07 PM UTC+8, Ben Bacarisse wrote:
>> meInvent bbird <jobmattcon@gmail.com> writes:
>> 
>> > parse error on input `\'
>> >
>> > import System.IO  
>> > import Control.Monad
>> >
>> > main = do
>> >   file <- readFile "hello.txt"
>> >   forM_ [5..7] (lines file) \i -> 
>> >       putStrLn i
>> 
>> Did you mean
>> 
>>   forM_ (lines file) (\i -> putStrLn i)
>> 
>> ?  The syntax error is that you need ()s round the lambda expression
>> here, but the extra list [5..7] is puzzling me.
>
> would like to choose specified lines to display

Then replace (lines file) with an expression that gives the lines you
want.  For example (take 2 (drop 4 (lines file)))  (which is neater
using $ but that's not the point).

-- 
Ben.

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