Re: nth field extraction

As I understand it you have several layers of delimiters. One idea for reusable code would be something that converts this into a multi-dimensional array -- one dimension per delimiter. E.g:

my $aref = &fieldParse($fullString, '!!', ';', ',');

sub fieldParse {
    my $source = shift;
    my $ret = [];
    my $delim = shift;
    defined($delim) or return $source;
    for (split $delim, $source) {
        push @$ret, &fieldParse($_, @_);
    }
    return $ret;
}
[download]

which produces:-

$VAR1 = [
          [
            [
              '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'
            ]
          ]
        ];
[download]

Updated (handle case of false-value delimiter as someone suggested)

One world, one people

Comment on Re: nth field extraction Select or Download Code

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Re^2: nth field extraction by AnomalousMonk (Archbishop) on Jul 27, 2018 at 20:51 UTC
`my $delim = shift or return $source;` This statement in `fieldParse()` makes me uneasy. The parse will fail if any `$*_div` is `'0'`. Perhaps unlikely, but still... A safer alternative IMHO would be: c:\@Work\Perl\monks>perl -wMstrict -MData::Dump -le "my $major_div = '!!'; my $user_div = '0'; my $var_div = ','; my $full_string = join $major_div, 'abcd-efgh-ijkl-mnop0key1=data1,key2=data20key1=data3,key2=data4', 'qwer-asdf-zxcv-tyui0key1=data30key3=data6', 'trew-hgfd-ytre-bvcx0key1=data7,key2=data80key1=data9,key2=data10', 'erty-dfgh-cvbn-hjkl0key2=data50key3=data6', ; print qq{full_string: <<$full_string>> \n}; ;; my $aref = fieldParse($full_string, $major_div, $user_div, $var_div); dd $aref; ;; sub fieldParse { my $source = shift; return $source unless @_; ;; my $delim = shift; return [ map fieldParse($_, @_), split $delim, $source ]; } " full_string: <<abcd-efgh-ijkl-mnop0key1=data1,key2=data20key1=data3,ke +y2=data4!!qwer-asdf-zxcv-tyui0key1=data30key3=data 6!!trew-hgfd-ytre-bvcx0key1=data7,key2=data80key1=data9,key2=data10!!e +rty-dfgh-cvbn-hjkl0key2=data50key3=data6>> [ [ ["abcd-efgh-ijkl-mnop"], ["key1=data1", "key2=data2"], ["key1=data3", "key2=data4"], ], [["qwer-asdf-zxcv-tyui"], ["key1=data3"], ["key3=data6"]], [ ["trew-hgfd-ytre-bvcx"], ["key1=data7", "key2=data8"], ["key1=data9", "key2=data1"], ], [["erty-dfgh-cvbn-hjkl"], ["key2=data5"], ["key3=data6"]], ] [download] (This version of the function still has some vulnerabilities, but I'm a bit more comfortable with it. :) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^2: nth field extraction by lee_crites (Scribe) on Jul 27, 2018 at 14:27 UTC
This is exactly the direction I was thinking of going! Thanks!!! I will be digesting this The problem I'm having is that I (re)process the string multiple times. That worked okay when I was doing it a few times -- perhaps several hundred or thousand times, total, in a run. But my best guess is that it will be run something between 1,500k and 3,000k times per run. Hence my hope for ideas on a better way. Just for giggles and grins, I extracted the function I had into a standalone test script. It was probably at the top of my coding about 15+ years ago. Here it is: #!/usr/bin/env perl my $which = 3; my $div = '!!!'; my $str = 'asdf' . $div . 'qwer' . $div . 'zxcv' . $div . 'hjkl' . $di +v . 'yuio' . $div . 'vbmn'; my @stuff; my $spot = 0; my $result = index($str, $div, $spot); print "str: [$str]\n"; while ($result != -1) { print "Found '$div' at $result\n"; my $start_spot = ($spot ? $spot + length($div) - 1 : 0); my $field_length = ($spot ? $result - $spot - length($div) + 1 : $ +result - $spot); push @stuff, substr($str, $start_spot, $field_length); $spot = $result + 1; $result = index($str, $div, $spot); } print @stuff . "\n"; print '-- #' . $which . '=' . @stuff[$which-1] . "\n"; [download] I am continually amazed and pleased at the quality of the responses I get/see here on perlmonks! Thanks, y'all!!! Lee Crites lee@critesclan.com	[reply] [d/l]
Re^3: nth field extraction by anonymized user 468275 (Curate) on Jul 30, 2018 at 14:37 UTC
In that case there could be a slight performance benefit in storing results in a hash, e.g. `my %res; ... ... for my $fullString (however they are obtained) { $res{$fullString} \|\|= fieldParse( $fullString, etc. ); etc... }` [download] One world, one people	[reply] [d/l]