Initial data commit

Task/Parsing-RPN-calculator-algorithm/FunL/parsing-rpn-calculator-algorithm.funl

@@ -0,0 +1,19 @@
+def evaluate( expr ) =
+  stack = []
+
+  for token <- expr.split( '''\s+''' )
+    case number( token )
+      Some( n ) ->
+        stack = n : stack
+        println( "push $token: ${stack.reversed()}" )
+      None ->
+        case {'+': (+), '-': (-), '*': (*), '/': (/), '^': (^)}.>get( token )
+          Some( op ) ->
+            stack = op( stack.tail().head(), stack.head() ) : stack.tail().tail()
+            println( "perform $token: ${stack.reversed()}" )
+          None -> error( "unrecognized operator '$token'" )
+
+  stack.head()
+
+res = evaluate( '3 4 2 * 1 5 - 2 3 ^ ^ / +' )
+println( res + (if res is Integer then '' else " or ${float(res)}") )