Online PHP editor | output for SDYiO

<?php $str = 'IF(1>10, "Large", "Medium") IF(1>10, IF(44>20, "Large", "Medium"), "Small") IF(1>10, IF(44>20, "Large", IF(4<5, "Tiny", "Medium")), "Small") IF(A1>10, IF(A1>20, "Large", IF(A1<5, "Tiny", "Medium")), "Small")'; $pattern =<<<'REGEX' ~ # subpatterns (?<string> " [^"\\]*+ (?s: \\. [^"\\]* )*+ " ){0} (?<nparens> $ [^"()]*+ (?: \g<string> [^"()]* | \g<nparens> [^"()]* )*+ $ ){0} (?<other> [^"()\s,] (?: [^"(),]* [^"()\s,])? ){0} (?<part> (?: \g<string> | \g<nparens> | \g<other> )* ){0} # main pattern IF$ \s* (\g<part>) \s* , \s* (\g<part>) \s*, \s* (\g<part>) \s* $ ~x REGEX; //$replacement = '($7) ? ($8) : ($9)'; $replacement = '($5) ? ($6) : ($7)'; do { $str = preg_replace($pattern, $replacement, $str, -1, $count); } while ($count); echo $str;