constructors.cs:
#    1| [NamespaceDeclaration] namespace ... { ... }
#    3|   1: [Class] Class
#    5|     4: [InstanceConstructor] Class
#    6|       4: [BlockStmt] {...}
#    8|     5: [InstanceConstructor] Class
#-----|       2: (Parameters)
#    8|         0: [Parameter] i
#    8|           -1: [TypeMention] int
#    9|       4: [BlockStmt] {...}
#   11|     6: [StaticConstructor] Class
#   12|       4: [BlockStmt] {...}
#   14|     7: [Destructor] ~Class
#   15|       4: [BlockStmt] {...}
#   16|         0: [LocalVariableDeclStmt] ... ...;
#   16|           0: [LocalVariableDeclAndInitExpr] Int32 i = ...
#   16|             -1: [TypeMention] int
#   16|             0: [LocalVariableAccess] access to local variable i
#   16|             1: [IntLiteral] 0
#   21| [NamespaceDeclaration] namespace ... { ... }
#   23|   1: [Class] C1
#   23|     4: [InstanceConstructor,PrimaryConstructor] C1
#-----|       2: (Parameters)
#   23|         0: [Parameter] o
#   23|           -1: [TypeMention] object
#   23|         1: [Parameter] s
#   23|           -1: [TypeMention] string
#   25|     5: [InstanceConstructor] C1
#-----|       2: (Parameters)
#   25|         0: [Parameter] o
#   25|           -1: [TypeMention] object
#   25|       3: [ConstructorInitializer] call to constructor C1
#   25|         0: [ParameterAccess] access to parameter o
#   25|         1: [StringLiteralUtf16] "default"
#   25|       4: [BlockStmt] {...}
#   28|   2: [Class] C2
#-----|     3: (Base types)
#   28|       0: [TypeMention] C1
#   28|     4: [InstanceConstructor,PrimaryConstructor] C2
#-----|       2: (Parameters)
#   28|         0: [Parameter] o
#   28|           -1: [TypeMention] object
#   28|         1: [Parameter] s
#   28|           -1: [TypeMention] string
#   28|         2: [Parameter] i
#   28|           -1: [TypeMention] int
#   28|       3: [ConstructorInitializer] call to constructor C1
#   28|         0: [ParameterAccess] access to parameter o
#   28|         1: [ParameterAccess] access to parameter s