Re^4: foreach type of deal?

Thanks! I just ran into that little bit :D.

However, I read the perldoc about substr, and I get the idea. Now my question is, what modifies the string? substr just locates the particular part of the string I want to single out, then what?

#!/usr/bin/perl

use strict;
use warnings;


main(@ARGV);

sub main
{
    
    open(FH, "gtype.txt");
    while( my $line = <FH> ) {
        my $line = substr($line,1);
        printf $line;
}

}

    close FH;
[download]

It works!! now what can I use to replace the printf, to use to delete?

Comment on Re^4: foreach type of deal? Download Code

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Re^5: foreach type of deal? by huck (Prior) on Mar 15, 2017 at 21:19 UTC
now what can I use to replace the printf, to use to delete? You have now entered a situation i dont like. You seem to want to want to replace the original file. for the most part i dont like to do that (at first). I dont like to modify my only copy of the original data. What i do instead is write a new file, then use the new file in later processing. `use strict; use warnings; main(@ARGV); sub main { open(my $in ,'<', "gtype.txt"); open(my $out ,'>', "fixed-gtype.txt"); while( my $line = <$in> ) { my $line = substr($line,1); print $out $line; } } close $in; close $out;` [download] Note also the change from printf to print. You should read about what printf does in regards to the first argument being a format. What you wanted instead was print.	[reply] [d/l]
Re^6: foreach type of deal? by hoagies (Initiate) on Mar 15, 2017 at 21:47 UTC
Wow, I'm thinking I have a lot to learn. I was with you until the in, out deal. I never even considered that I had to use something like that. You're right, I shouldn't have been thinking about making a change to the original copy. I tried the code, and it works, but it will only work if I comment out use strict mode. Otherwise, I'm getting errors on declarations. I'm currently trying to figure out how to declare this code correctly. As I said, the code works like a charm, but I want to see if I can at least get the declarations correct. :/. I learned a few things with this, but I wouldn't have come close to figuring this out without you guys. Thanks!	[reply]
Re^7: foreach type of deal? by huck (Prior) on Mar 15, 2017 at 21:50 UTC
ug... will "too early in the morning" work at 4pm? `while( my $line = <$in> ) { $line = substr($line,1); print $out $line; }` [download]	[reply] [d/l]
Re^8: foreach type of deal? by hoagies (Initiate) on Mar 15, 2017 at 22:26 UTC
Re^5: foreach type of deal? by kennethk (Abbot) on Mar 15, 2017 at 21:46 UTC
Subject to huck's well placed concerns about moving files on lists that haven't been manually inspected, look up rename or File::Copy. It's very easy to use these powerful tools to torpedo yourself. #11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.	[reply]


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