Q2 prep

Q2/Artefacts/fspow.g4

@@ -0,0 +1,62 @@
+grammar fspow;
+// workshop 4 version
+
+prog:   stat+ ;
+
+// labelling alternatives creates extra visitor methods
+// the labels migh clash with rule names, so I make them unique
+stat:
+        assignment      # statAssignment 
+    |   fcList          # statFcList
+    |   fcApplySelector # statFcApplySelector
+    |   message         # statMessage
+    ;
+
+assignment :
+    ID '=' expression ;
+    
+// when alternatives are introduced, try using labels to distinguish
+expression : 
+    ID              # exprID
+    |
+    selCreation     # exprSelCreation 
+    |
+    fcCreation   # exprFcCreation
+    ;
+// -------
+// filecollection statements    
+// -------
+fcCreation:         fcCreationName '(' rootSpecifier ')' ;
+
+fcCreationName:     'FileCollection' ;
+rootSpecifier:      STRING ;
+// -------
+// selector statements    
+// -------
+selCreation :       selCreationName '(' filterSpecifier ')' ;
+
+selCreationName:    'Selector' ; 
+filterSpecifier:    selfilter '(' STRING ')' ;
+selfilter:          'name' ;     
+// -------
+// apply statement    
+// -------
+fcApplySelector:    ID '.' applyName '(' expression ')' ;
+
+applyName:          'apply' ;
+// -------
+// print statement    
+// -------
+fcList:             ID '.' printName ;
+
+printName:          'print()' ;
+// -------
+// message statement    
+// -------
+message: 'message' STRING ;
+
+ID:         [a-zA-Z][a-zA-Z0-9]* ;
+STRING:     '"'.*?'"'     
+    {self.text = self.text[1:-1]} ;
+WS :        [ \t\r\n]+ -> skip ;
+COMMENT :   '//' ~[\r\n]* -> channel(HIDDEN) ;