Parse strings as 'foo'

Author: DeLaGuardo

src/axel_f/core.cljc

@@ -38,7 +38,7 @@ ARRAY_EXPR               ::= <opening-curly-bracket> ( EXPR {<comma> EXPR} )? <c
 ERROR                    ::= #'#N/A|#VALUE!|#REF!|#DIV/0!|#NUM!|#NAME?|#NULL!'
 CONST                    ::= NUMBER | STRING | BOOL
 NUMBER                   ::= #'[0-9]+\\.?[0-9]*(e[0-9]+)?'
-STRING                   ::= #'\"[^\"]*\"'
+STRING                   ::= #'\"[^\"]*\"' | #\"'[^']*'\"
 BOOL                     ::= #'TRUE|FALSE|True|False|true|false'
 FNCALL                   ::= FN <opening-parenthesis> ARGUMENTS <closing-parenthesis>
 FN                       ::= " (-> functions/functions-map