<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /></head><body style='font-size: 10pt; font-family: Verdana,Geneva,sans-serif'>
<blockquote type="cite" style="padding: 0 0.4em; border-left: #1010ff 2px solid; margin: 0">
<div class="pre" style="margin: 0; padding: 0; font-family: monospace">When did it become common for people to write halachah seforim on a single topic? It may just be too late at night,<br /> but I can't think of a single example offhand. Is it possible that the CC's<br /> pioneering look at Lashon Hara was not only that he pioneered looking at<br /> it, but that he was a pioneer of what we would call today (in Lakewood, at<br /> least), "specializing in a miktzo'a"?</div>
</blockquote>
<p>I could easily be mistaken, but I thought this was not uncommon at all during the pre-S"A days. Whether common or not, the Ramban wrotes some. Encyclopedia Judaica notes: "Naḥmanides' known halakic works are: "Mishpeṭe ha-Ḥerem," the laws concerning excommunication, reproduced in "Kol Bo"; "Hilkot Bediḳah," on the examination of the lungs of slaughtered animals, cited by Simeon ben Ẓemaḥ Duran in his "Yabin Shemu'ah"; "Torat ha-Adam," on the laws of mourning and burial ceremonies, in thirty chapters, the last of which, entitled "Sha'ar ha-Gemul," deals with eschatology"</p>
<p>FWIW,</p>
<p>-- Sholom</p>
</body></html>