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Converting one-liner to script

vid401t
New User

Nov 7, 2012, 4:53 AM

Post #1 of 6 (3773 views)

Converting one-liner to script	Can't Post

Hi Everyone,

I'm trying to convert the following one liner into a perl script:
perl -ne 'chomp; print join(".", splice(@{[split/\./,$_]}, 0, -1), map {++$_} pop @{[split/\./,$_]}), "\n";'

What it does:

Code

$ cat versions 
1.2.3.44 
1.2.3.9 
1.2.3 
9

Code

$ cat versions | perl -ne 'chomp; print join(".", splice(@{[split/\./,$_]}, 0, -1), map {++$_} pop @{[split/\./,$_]}), "\n";' 
1.2.3.45 
1.2.3.10 
1.2.4 
10

I've tried using perl -MO=Deparse and inputting the code as follows into my script:

Code

$test = "1.2.4"; 
 
chomp $test; 
print join('.', splice(@{[split(/\./, $test, 0)];}, 0, -1), map({++$test;} pop @{[split(/\./, $test, 0)];})), "\n";

But it keeps outputting: 1.2.2.2 <-- incorrect, should be 1.2.5

Any ideas or help?
Much appreciated in advance.

BillKSmith
Veteran

Nov 7, 2012, 6:59 AM

Post #2 of 6 (3767 views)

Re: [vid401t] Converting one-liner to script [In reply to]	Can't Post

The easy way to convert you one-liner to a script is to put it in a file. Add the #! line to specify the path and flags.

Code

#!/usr/bin/perl -n 
    chomp; 
    print join( ".", 
        splice( @{ [ split /\./, $_ ] }, 0, -1 ), 
        map { ++$_ } pop @{ [ split /\./, $_ ] } ), 
        "\n" 
    ;

A less error prone way to increment version numbers is:

Code

#!/usr/bin/perl -n 
use strict; 
use warnings; 
chomp; 
my @array = split /\./; 
$array[-1]++; 
join '.', @array; 
local $" = '.'; 
print "@array\n";

In either case you could run them much like the one-liner.

Code

cat versions | perl script.pl 
 
or 
 
perl script.pl < versions

Good Luck,
Bill

vid401t
New User

Nov 7, 2012, 10:39 AM

Post #3 of 6 (3761 views)

Re: [BillKSmith] Converting one-liner to script [In reply to]	Can't Post

Hey Bill,

Thanks for the reply, much appreciated.

Last question, what if I was trying to use a string within the perl file to increment, how would that look?

Example:

Code

#!/usr/bin/perl -n  
use strict;  
use warnings;  
 
my $testString = "1.2.3"; 
 
# Below is not working for me as I get no output 
my @array = split(/\./, $testString);  
$array[-1]++;  
local $" = '.';  
print "@array\n";

Thanks again!

In Reply To

Laurent_R
Veteran / Moderator

Nov 7, 2012, 10:41 AM

Post #4 of 6 (3760 views)

Re: [vid401t] Converting one-liner to script [In reply to]	Can't Post

BTW, you don't need this convoluted syntax:

Code

cat versions | perl ...

but you can simply run the one-liner on the file:

Code

perl -ne 'chomp; print join(".", splice(@{[split/\./,$_]}, 0, -1), map {++$_} pop @{[split/\./,$_]}), "\n";' versions

BillKSmith
Veteran

Nov 7, 2012, 11:16 AM

Post #5 of 6 (3758 views)

Re: [vid401t] Converting one-liner to script [In reply to]	Can't Post

Remove the -n from the #! line.
Good Luck,
Bill

(This post was edited by BillKSmith on Nov 7, 2012, 12:02 PM)

vid401t
New User

Nov 7, 2012, 11:48 AM

Post #6 of 6 (3755 views)

Re: [BillKSmith] Converting one-liner to script [In reply to]	Can't Post

Awesome!! thank you guys, worked out well, very helpful community btw, hope to get better at this and eventually help others out as well.

thanks again!

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