use strict;
my $str = '
I have been analyzing large amounts of text data. This is what I got so far:
(([A-Z][\\w-]*)+\\s+(\\b(Study|Test)\\b)(\\s[A-Z][\\w-]*)*)|(\\b(Study|Test)\\b)(\\s[A-Z][\\w-]*)+
Types of phrases I would like to capture:
Europe National Longitudinal Study
Longitudinal Study
Study Initiative
Longitudinal Study Initiative
I want to capture the word \'Study\' or \'Test\' ONLY if it is surrounded by the words starting with a capital letter. The ideal regex would achieve all of this + it would ignore\\escape certain words like \'of\' or \'the\'.
*the above regex is super slow with the str.findall function, I guess there must be a better solution
** I used https://regex101.com for testing and then run it in Jupyter, Python 3
';
my $regex = qr~(?(DEFINE)
(?<marker>\b[A-Z][-\w]*\b)
(?<ws>[\ \t]+)
(?<needle>\b(?:Study|Test))
(?<pre>(?:(?&marker)(?&ws))+)
(?<post>(?:(?&ws)(?&marker))+)
(?<before>(?&pre)(?&needle))
(?<after>(?&needle)(?&post))
(?<both>(?&pre)(?&needle)(?&post))
)
(?&both)|(?&before)|(?&after)~mxp;
if ( $str =~ /$regex/g ) {
print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n";
# print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n";
# print "Capture Group 2 is $2 ... and so on\n";
}
# ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p'
# Named capture groups can be called via $+{name}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html