jack_64 has asked for the wisdom of the Perl Monks concerning the following question:

Hi monks im trying to complete my homework but i got stuck in between...This is my 2 nd week of learning perl and im not very good wiht regex...Im trying to extract some text from a C file and im writing to a .doc file.. 

The C file format is

Function: stdio.h
Input: None
Output : Performs Standard input output operations

<Some Code here>

Function: math.h
Input: Mathematical operators
Ouput: Performs mathematical operations
<Some Code here>

[download]

The output in the .doc file should be like this

Function: stdio.h
Output:
Performs Standard input output operations
Input:
None

Function: math.h
Output:
Performs mathematical operations
Input:
Mathematical operators

[download]

Im have written a snippet to open MS Word and read the .c file and extract the function name and the snippet is below:- 

use warnings;
use Win32::OLE;
use Win32::OLE qw(in with);
use Win32::OLE::Variant;
use Win32::OLE::Const 'Microsoft Excel';
use Win32::OLE::Const 'Microsoft Word'; 
use Cwd;
use File::Find;

//MS Word Opening
my $word = CreateObject Win32::OLE 'Word.Application' or die $!;
$word->{'Visible'} = 1;
my $document = $word->Documents->Add;
my $selection = $word->Selection;

my @scriptfiles;
my $text;
my @array;
our $file;

@scriptfiles=glob('*.c');
foreach $file (glob('*.c'))
{ 
    open(my $fh, $file) or die("Unable to open '$file': $!");  
    while (my $line = <$fh>)
    {
        if ($line =~ /Function:\s*(.+)/ )
        {
            $selection -> TypeText($line); 
        }
    }
    
    }

[download]

The issue is how to extract the Input and output from the .c file. Im extracting Function name first then i have to extract Output and then input..im currently reading the .c file ($line = <$fh>) and searching for the function name how to do the same for Output and Input..pls teach me thanks...

Replies are listed 'Best First'.
Re: Understanding Regex
by aaron_baugher (Curate) on Jun 10, 2012 at 12:15 UTC

    First of all, you're processing a text file, so leave the MS Word stuff out of it. That's unnecessary and complicating things, as far as I can tell. I can see two ways to do this:

    Process the file line-by-line, watching for lines starting with Function:. When you hit one, print it, then read in the next line (Input:) and save it, then read in the next line (Output:), stick a newline after the first colon, print it, then do the same with the Input: line you saved and print it, then print a new line. Start watching for a Function: line again.

    The other way: read the whole thing into a single scalar variable, then write a regex to match the chunks of text that you're looking for, and loop through those chunks, printing out what you find in the format you want. Something like this (assumes a couple typos in your example):

    while( $str =~ /(Function: .+?)\nInput: (.+?)\nOutput: (.+?)\n/gs ){
    print <<END;
$1
Output:
$2
Input:
$3

END
}

    [download]

    In many languages you'd have no choice but to use the first method, which requires more programming logic. Perl's regexes are so powerful that you can replace a lot of logic with one big pattern match.

    Aaron B.
    Available for small or large Perl jobs; see my home node.

[reply]
[d/l]
[select]
Re: Understanding Regex
by pRaNaV (Novice) on Jun 10, 2012 at 12:03 UTC

    Hi, Let's say you want to extract 'output' info, then you can write code like below

     
if($line =~ /^Ouput/) {
    chomp $line; #To delete any newline character at the end of line t
+o appear in outputInfo
    my $outputInfo = $line; 
    $outputInfo =~ s/^Ouput: //;
    print "\n$outputInfo";
}

    [download]
[reply]
[d/l]
Re: Understanding Regex
by Anonymous Monk on Jun 10, 2012 at 10:33 UTC

    A homework assignment trying to teach regex and Win32::OLE at the same time? Unlikely story

[reply]

Back to Seekers of Perl Wisdom