I may have misunderstood what you are asking for, but I think the solution to your problem is look-ahead assertions. 

m< 
  (?:            # A char that is:
   [^\$]         #   Not a $
   |             #   Or
   \$ (?! {= )   #   A $ not followed by {=
  )+             # Many times
>x;

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In reply to Re: Regex matching next occurrence or to the end of line. by Eily
in thread Regex matching next occurrence or to the end of line. by nabeenj

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