1  
 2  [replacements]
 3  
 4  # Arrows from the Arrows block of Unicode.
 5  # -> right arrow
 6  (?<!\\)-&gt;=-&gt;
 7  \\-&gt;=-&gt;
 8  # => right double arrow
 9  (?<!\\)\=&gt;==&gt;
10  \\\=&gt;==&gt;
11  # <- left arrow
12  (?<!\\)&lt;-=&lt;-
13  \\&lt;-=&lt;-
14  # <= left double arrow
15  (?<!\\)&lt;\==&lt;=
16  \\&lt;\==&lt;=