Maps and sets defined by extension are now general expressions.

They used to be allowed only as initial values in declarations.
This new syntax enables idioms like

if set ["John"; "Paul"] contains x then ... else

Parser.mly

@@ -417,10 +417,6 @@ unqualified_decl(OP):
                opt_type = $3};
              rpar = Region.ghost}
            in EConstr (NoneExpr {region; value})
-      | `EMap inj ->
-          EMap (MapInj inj)
-      | `ESet inj ->
-          ESet (SetInj inj)
     in $1, $2, $3, $4, init, $6, stop
   }
 
@@ -457,12 +453,9 @@ var_decl:
   }
 
 extended_expr:
-  expr          { {region = expr_to_region $1;
+  expr   { {region = expr_to_region $1; value  = `Expr $1} }
-                   value  = `Expr $1} }
 | Nil    { {region = $1; value = `EList $1} }
 | C_None { {region = $1; value = `ENone $1} }
-| map_injection { {region = $1.region; value = `EMap $1} }
-| set_injection { {region = $1.region; value = `ESet $1} }
 
 instruction:
   single_instr { Single $1 }
@@ -936,6 +929,7 @@ core_expr:
 | none_expr        { EConstr (NoneExpr $1)        }
 | fun_call         { ECall $1                     }
 | map_expr         { EMap $1                      }
+| set_expr         { ESet $1                      }
 | record_expr      { ERecord $1                   }
 | projection       { EProj $1                     }
 | Constr arguments {
@@ -947,8 +941,12 @@ core_expr:
     EConstr (SomeApp {region; value = $1,$2})
   }
 
+set_expr:
+  set_injection { SetInj $1 }
+
 map_expr:
   map_lookup    { MapLookUp $1 }
+| map_injection {    MapInj $1 }
 
 map_lookup:
   path brackets(expr) {

Tests/crowdfunding.ligo

@@ -28,6 +28,7 @@ entrypoint withdraw (storage store : store; const sender : address)
   : store * list (operation) is
   var operations : list (operation) := list end
   begin
+//    if set ["a"; "b"] contains x then skip else skip;
     if sender = owner then
       if now (Unit) >= store.deadline then
         if balance >= store.goal then {