Nth Field Extraction

I am hoping for some ideas from the wonderful collective on how to do something better than I am currently doing it. Here is the issue: I need a function (it will eventually replace the one in an package I have) that will be passed a delimiter string, the count, and the source string, and return the string in the count'th field.

I cannot use split() because the delimiter might be multiple characters, and it comes in via a variable. I currently use a while loop with index, building an array with the starting positions of each field, and then use substr to grab out what I am looking for. Here is an example:

my $major_div = '!!';
my $user_div = ';';
my $var_div = ',';
my $full_string = 'abcd-efgh-ijkl-mnop;key1=data1,key2=data2;key1=data
+3,key2=data4!!qwer-asdf-zxcv-tyui;key1=data3;key3=data6!!trew-hgfd-yt
+re-bvcx;key1=data7,key2=data8;key1=data9,key2=data10!!erty-dfgh-cvbn-
+hjkl;key2=data5;key3=data6';

my $major_field = &field_split($major_div, 3, $full_string);
my $user_key = &field_split($user_div, 1, $major_field);
my $user_vars1 = &field_split($user_div, 2, $major_field);
my $user_vars2 = &field_split($user_div, 3, $major_field);
my $key_data = &field_split($var_div, 1, $user_vars1);

[download]

The example is rather ludicrous, I admit, but it shows what we are doing. Sometimes what we are doing is iterating over the string (the major fields), and processing them all, one at a time.

I have something that works, but the code is a dozen years old, and I have wanted to update it, but just haven't done it -- if it ain't broke, don't fix it, right? But this new task will be using the code a lot, so I'm hoping one of you perl masters have already tuned a function that does this, and would be willing to share it.

Thanks muchly!

David Lee Crites
lee@critesclan.com

In reply to nth field extraction by lee_crites

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