When does RAM become an issue?

Sooner or later

How would I adapt this solution to refer to a separate input file?

Read perlintro you can't skip that

What would be the best reference source, for purposes of interpreting the few Perl codes suggested in that solution?

Combine ppi_dumper with Perl documentation / Modern Perl and super search/Tutorials... 

$ ppi_dumper code.pl
PPI::Document
  PPI::Token::Comment      '#! perl -slw\n'
  PPI::Statement::Include
    PPI::Token::Word      'use'
    PPI::Token::Whitespace      ' '
    PPI::Token::Word      'strict'
    PPI::Token::Structure      ';'
  PPI::Token::Whitespace      '\n'
  PPI::Token::Whitespace      '\n'
  PPI::Statement::Variable
    PPI::Token::Word      'my'
    PPI::Token::Whitespace      ' '
    PPI::Token::Symbol      '@array'
    PPI::Token::Whitespace      ' '
    PPI::Token::Operator      '='
    PPI::Token::Whitespace      ' '
    PPI::Token::Word      'split'
    PPI::Token::Whitespace      ' '
    PPI::Token::Quote::Single      ''term''
    PPI::Token::Operator      ','
    PPI::Token::Whitespace      ' '
    PPI::Token::Word      'do'
    PPI::Structure::Block      { ... }
      PPI::Token::Whitespace      ' '
      PPI::Statement::Variable
        PPI::Token::Word      'local'
        PPI::Token::Whitespace      ' '
        PPI::Token::Magic      '$/'
        PPI::Token::Structure      ';'
      PPI::Token::Whitespace      ' '
      PPI::Statement
        PPI::Token::Operator      '<'
        PPI::Token::Word      'DATA'
        PPI::Token::Operator      '>'
      PPI::Token::Whitespace      ' '
    PPI::Token::Structure      ';'
  PPI::Token::Whitespace      '\n'
  PPI::Statement
    PPI::Token::Word      'shift'
    PPI::Token::Whitespace      ' '
    PPI::Token::Symbol      '@array'
    PPI::Token::Structure      ';'
  PPI::Token::Whitespace      ' '
  PPI::Token::Comment      '## Discard leading null'
  PPI::Token::Whitespace      '\n'
  PPI::Token::Whitespace      '\n'
  PPI::Statement
    PPI::Token::Word      'print'
    PPI::Token::Whitespace      ' '
    PPI::Token::Quote::Single      ''---''
    PPI::Token::Operator      ','
    PPI::Token::Whitespace      ' '
    PPI::Token::Quote::Double      '"\n"'
    PPI::Token::Operator      ','
    PPI::Token::Whitespace      ' '
    PPI::Token::Magic      '$_'
    PPI::Token::Operator      ','
    PPI::Token::Whitespace      ' '
    PPI::Token::Quote::Double      '"\n"'
    PPI::Token::Whitespace      ' '
    PPI::Token::Word      'for'
    PPI::Token::Whitespace      ' '
    PPI::Token::Symbol      '@array'
    PPI::Token::Structure      ';'
  PPI::Token::Whitespace      '\n'
  PPI::Token::Whitespace      '\n'
  PPI::Statement::Data
    PPI::Token::Separator      '__DATA__'
    PPI::Token::Whitespace      '\n'
    PPI::Token::Data      'term {\nyada yada\n12345\n() ...\n}\n\nterm
+ only occurs here {\ncould be 30 lines here\nbut never that word agai
+n until\nanother block starts\nyadada\n}\n\nterm, etc.'

[download]

So operator, __DATA__, local, $_, $_...

Which version of Perl should I install, to run this code?

It will run on any perl that starts with a "5." , anything released in the last 20+ years

In reply to Re: Learning Perl by Doing by Anonymous Monk
in thread Learning Perl by Doing by raywood

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