initializers.cs:
#    3| [Class] S1
#    5|   5: [Field] P1
#    5|     -1: [TypeMention] int
#    6|   6: [Property] P2
#    6|     -1: [TypeMention] int
#    6|     3: [Getter] get_P2
#    6|     4: [Setter] set_P2
#-----|       2: (Parameters)
#    6|         0: [Parameter] value
#    7|   7: [Property] P3
#    7|     -1: [TypeMention] int
#    7|     3: [Setter] set_P3
#-----|       2: (Parameters)
#    7|         0: [Parameter] value
#    7|       4: [BlockStmt] {...}
#   10| [Class] S2
#-----|   3: (Base types)
#   10|     1: [TypeMention] IEnumerable
#   12|   5: [Method] Add
#   12|     -1: [TypeMention] Void
#-----|     2: (Parameters)
#   12|       0: [Parameter] x
#   12|         -1: [TypeMention] int
#   12|     4: [BlockStmt] {...}
#   13|   6: [Method] Add
#   13|     -1: [TypeMention] Void
#-----|     2: (Parameters)
#   13|       0: [Parameter] x
#   13|         -1: [TypeMention] int
#   13|       1: [Parameter] y
#   13|         -1: [TypeMention] int
#   13|     4: [BlockStmt] {...}
#   14|   7: [Method] GetEnumerator
#   14|     -1: [TypeMention] IEnumerator
#   14|     4: [BlockStmt] {...}
#   14|       0: [ReturnStmt] return ...;
#   14|         0: [NullLiteral] null
#   17| [Class] Test
#   19|   5: [Method] Main
#   19|     -1: [TypeMention] Void
#-----|     2: (Parameters)
#   19|       0: [Parameter] args
#   19|         -1: [TypeMention] String[]
#   19|           1: [TypeMention] string
#   20|     4: [BlockStmt] {...}
#   21|       0: [ExprStmt] ...;
#   21|         0: [ObjectCreation] object creation of type S1
#   21|           -2: [TypeMention] S1
#   21|           -1: [ObjectInitializer] { ..., ... }
#   21|             0: [MemberInitializer] ... = ...
#   21|               0: [FieldAccess] access to field P1
#   21|               1: [IntLiteral] 1
#   21|             1: [MemberInitializer] ... = ...
#   21|               0: [PropertyCall] access to property P2
#   21|               1: [IntLiteral] 2
#   21|             2: [MemberInitializer] ... = ...
#   21|               0: [PropertyCall] access to property P3
#   21|               1: [IntLiteral] 3
#   22|       1: [ExprStmt] ...;
#   22|         0: [ObjectCreation] object creation of type S2
#   22|           -2: [TypeMention] S2
#   22|           -1: [CollectionInitializer] { ..., ... }
#   22|             0: [ElementInitializer] call to method Add
#   22|               0: [IntLiteral] 1
#   22|             1: [ElementInitializer] call to method Add
#   22|               0: [IntLiteral] 2
#   22|             2: [ElementInitializer] call to method Add
#   22|               0: [IntLiteral] 3
#   22|             3: [ElementInitializer] call to method Add
#   22|               0: [IntLiteral] 4
#   22|               1: [IntLiteral] 5