================================================================================
Struct with a type parameter struct constraint
================================================================================

public struct F<T> where T:struct {}

public struct F<T> where T: new() {}

readonly public struct A : ISomething { }

private struct F<T1,T2> where T1 : I1, I2, new() where T2 : I2 { }

ref struct Test { }

struct NoBody;

private struct NoBodyWithPrimary(int g);
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(compilation_unit
  (struct_declaration
    (modifier)
    name: (identifier)
    (type_parameter_list
      (type_parameter
        name: (identifier)))
    (type_parameter_constraints_clause
      (identifier)
      (type_parameter_constraint))
    body: (declaration_list))
  (struct_declaration
    (modifier)
    name: (identifier)
    (type_parameter_list
      (type_parameter
        name: (identifier)))
    (type_parameter_constraints_clause
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      (type_parameter_constraint
        (constructor_constraint)))
    body: (declaration_list))
  (struct_declaration
    (modifier)
    (modifier)
    name: (identifier)
    (base_list
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    body: (declaration_list))
  (struct_declaration
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    name: (identifier)
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        name: (identifier)))
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      (type_parameter_constraint
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      (type_parameter_constraint
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    (type_parameter_constraints_clause
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        type: (identifier)))
    body: (declaration_list))
  (struct_declaration
    name: (identifier)
    body: (declaration_list))
  (struct_declaration
    name: (identifier))
  (struct_declaration
    (modifier)
    name: (identifier)
    (parameter_list
      (parameter
        type: (predefined_type)
        name: (identifier)))))
