Is there a function that checks if a specific character sequence - "abc" - is on a line and puts point there if it is? And returning something (presumably nil) if "abc" isn't on the current line?
No, but it's easy to write one (guaranteed 100% untested):
(defun search-like-alex-seems-to-want (regexp) (let ((pos (save-excursion (forward-line 0) ;; Go to BOL. (re-search-forward regexp (line-end-position) t)))) (when pos (goto-char pos)) pos))