Added more docs for no-octal (#114)

* Added more docs for `no-octal`

* Typo

Author: RunDevelopment

docs/rules/no-octal.md

@@ -13,9 +13,11 @@ since: "v0.1.0"
 
 ## :book: Rule Details
 
-This rule reports octal escape.
+This rule reports octal escapes.
 
-`\0` is matches a `NUL` character. Do not follow this with another digit, because a 0 followed by a number is an octal escape sequence.
+`\0` matches the `NUL` character. However, if `\0` is followed by another digit, it will become an octal escape sequence (e.g. `\07`).
+
+Octal escapes can also easily be confused with backreferences. The same character sequence (e.g. `\3`) can either escape a character or be a backreference depending on the number of capturing groups in the pattern. E.g. the `\2` in `/(a)\2/` is a character but the `\2` in `/(a)(b)\2/` is a backreference. This can be a problem when refactoring regular expressions because an octal escape can become a backreference or vice versa.
 
 <eslint-code-block>
 
@@ -25,9 +27,11 @@ This rule reports octal escape.
 /* ✓ GOOD */
 var foo = /\0/;
 var foo = /=/;
+var foo = /(a)\1/;
 
 /* ✗ BAD */
 var foo = /\075/;
+var foo = /\1/;
 ```
 
 </eslint-code-block>