Capturing parens force the entire document to be copied (slow)

Can you explain?
Where and why does this happen?

In reply to Re^2: How would you parse this? (rec-descent) by smls
in thread How would you parse this? by BrowserUk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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