In your second post, you split your summary into lines

my @split = split /\n/, $summary;

However your expected result contains multiple lines. The regex matches the beginning of the next line starting with [[ - and as the [[ occurs in the first column, that match is empty.

Try to work on your original data, not the line-by-line-version, e.g. by replacing

if (/\Q[[$article_name]]\E(.*?)\[\[/s) {

with

if ($summary =~ /\Q[[$article_name]]\E(.*?)\[\[/s  {

In reply to Re^3: Regex to catch UP TO a particular string? by Ratazong
in thread Regex to catch UP TO a particular string? by ultranerds

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