Are there any easy ways to implement this function?
Yes of course. Write a subroutine which takes the following parameters: the variable that contains one line of data, the separator and a list of numbers (zero based!) of the columns to return. The subroutine returns a list containing the selected fields which you can save in an array. The subroutine returns a string of the fields extracted, joined by the same separator.

All you have to do now is write the body of this subroutine.

See how easy it is:

use Modern::Perl;

sub extract {
    my ($data, $separator, @fields) = @_;
    return join $separator, (split(/$separator/, $data))[@fields];
}

my $input = 'First#second#third#and this is field no. 4#FIVE5five5#all
+ sixes 666#Seventh and last';
my $extraction = extract($input, '#', 1, 3, 4, 6);
say $extraction;

[download]
The subroutine does not do any error checking of the input parameters and will not deal correctly with escaped separators or quoted fields.

Update: I added a code example.

Update 2: amended the code example to return a string rather than a list

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re: Perl Substr by CountZero
in thread Perl Substr by lddzjwwy

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