Hello Cristoforo,

Within the look-ahead assertion (?=$), the metacharacter $ means:

Match the end of the string (or before newline at the end of the string; or before any newline if /m is used) (from “Metacharacters” in perlre#The-Basics)

Since it comes after the newline within the regex pattern — and your string contains no consecutive newlines — it can match only at the very end of the string. This explains the behaviour you’re seeing.

If you remove the look-ahead:

for my $line (split/(?m)\n/, $s) {

[download]

the output is displayed line-by-line, as expected.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: matching lines in a long string by Athanasius
in thread matching lines in a long string by Cristoforo

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