Inquiry: Javascript and Webcrawlers

[frankosport19]

Greetings ....

With regards to the following two javascript protocols  (in larger bold letters) ...

»»   <a href="javascript: void(0)" onclick="location.href='somesite.worldwideweb'">somesite</a>

»» document.write("<a href="somesite.worldwideweb">somesite</a>");

... my question is what effect do either of these have on web-crawler robots from the likes of Google, Bing or archive-dot-org's Wayback Machine ?? Do either or both of  these  keep a crawler from recording and following the particular link or not ??

Regarding pages that automatically re-direct to other pages using Javascript, would these also be crawler deterrents ?? FYI - I currently use a Javascript that erases mention of the re-directing page from a web-browser's history.

I should point out that I am already aware of other web-crawler deterrent methods, such as "disallow" in robots.txt; the META tags noindex, nofollow; non-publicly accessible pages; password-protected pages and folders.

Thanx-A-Lot. Stay Safe and Well.

Edited February 12, 2021 by frankosport19
Additional Info and protocol correction

[Ingolme]

Neither of those guarantee that the link won't be crawled. Crawlers are pretty intelligent these days.

If you don't want your link crawled, add a rel="nofollow" attribute to the <a> element.