typo

patterns.md

 
 `<statement>` ::= `<actions>` `<ws>` "if" `<ws>` `<expression>`
 
-`<ws>` ::= SPACE | TAB | CR | LF | <ws> <ws>
+`<ws>` ::= SPACE | TAB | CR | LF | `<ws>` `<ws>`
 
 `<actions>` ::= `<action>` | `<action>` `<ws>` `<actions>`