================================================================================
Scoped function calls
================================================================================

int main() {
  abc::def("hello", "world");
}

--------------------------------------------------------------------------------

(translation_unit
  (function_definition
    (primitive_type)
    (function_declarator
      (identifier)
      (parameter_list))
    (compound_statement
      (expression_statement
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          (qualified_identifier
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            (identifier))
          (argument_list
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              (string_content))
            (string_literal
              (string_content))))))))

================================================================================
Compound literals without parentheses
================================================================================

T x = T{0};
U<V> y = U<V>{0};
int x = int{1};

--------------------------------------------------------------------------------

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        (primitive_type)
        (initializer_list
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================================================================================
Explicit destructor calls
================================================================================

int main() {
  foo.~Foo();
  bar->~Bar();
}

--------------------------------------------------------------------------------

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      (expression_statement
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            (identifier)
            (destructor_name
              (identifier)))
          (argument_list))))))

================================================================================
New and Delete expressions
================================================================================

int main() {
  auto a = new T();
  auto b = new U::V<W, X>{};
  auto c = new (&d) T;
  auto d = new T[5][3]();
  auto e = new int[5];
  d = new(2, f) T;
  delete a;
  ::delete[] c;
  ::new (foo(x)) T(this, x);
}

--------------------------------------------------------------------------------

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              (identifier)
              (argument_list
                (identifier))))
          (type_identifier)
          (argument_list
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            (identifier)))))))

================================================================================
Initializer lists as arguments
================================================================================

int main() {
  pairs.push_back({true, false});
}

--------------------------------------------------------------------------------

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    (function_declarator
      (identifier)
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      (expression_statement
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            (field_identifier))
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              (false))))))))

================================================================================
Lambda expressions
================================================================================

auto f = [&](int x) -> bool {
  return true;
};

auto g = [x, y](int z) {
  return false;
};

auto h = [] {
  return false;
};

auto i = [] <typename T> () {
  return T();
};

auto i = [] <typename T> requires Hashable<T> {
  return T();
};

--------------------------------------------------------------------------------

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        (compound_statement
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================================================================================
Nested template calls
================================================================================

class A {
  A() : T::template Nested<int>::type() {}
  A() : T::template Nested<int>::template Nested2<float>::type() {}

  B<C::D<E, F>>::G field;
  using B<C>::template D<int>;

  H<I<J>> method() {
    K::L<M<N>> variable1 = K::L<M<N>>{};
    typename K::template L<M<N>>::type variable2;
    typename K::template L<M<N>>::template O<P>::type variable3;
  }

  typename Z::template Nested<int>::type x;
  typename X::template Nested<int>::Y::template Nested2<D> x;
};

--------------------------------------------------------------------------------

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        (field_identifier)))))

================================================================================
Comma expressions at the start of blocks
================================================================================

int main() { a(), b(); }

--------------------------------------------------------------------------------

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          (call_expression
            (identifier)
            (argument_list)))))))

================================================================================
Nullptr
================================================================================

void *x = nullptr;

--------------------------------------------------------------------------------

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        (identifier))
      (null))))

================================================================================
Raw string literals
================================================================================

const char *s1 = R"(
  This is a string. It ends with ')' and a quote.
)";

const char *s2 = R"FOO(
  This is a string. It ends with ')FOO' and a quote.
)FOO";

const char *s3 = uR"FOO(
  This is a string. It ends with ')FOO' and a quote.
)FOO";

const char *s4 = UR"FOO(
  This is a string. It ends with ')FOO' and a quote.
)FOO";

const char *s5 = u8R"FOO(
  This is a string. It ends with ')FOO' and a quote.
)FOO";

const char *s6 = LR"FOO(
  This is a string. It ends with ')FOO' and a quote.
)FOO";

--------------------------------------------------------------------------------

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    (primitive_type)
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      (raw_string_literal
        (raw_string_delimiter)
        (raw_string_content)
        (raw_string_delimiter)))))

================================================================================
Template calls
================================================================================

int main() {
  // '<' and '>' as template argument list delimiters
  if (a<b && c>()) {}

  // '<' and '>' as binary operators
  if (a < b && c >= d) {}

  Q::template R<S>();
  this->template f<T>();
  foo.template f<U>();
}
--------------------------------------------------------------------------------

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                  (type_descriptor
                    (type_identifier))))))
          (argument_list))))))

================================================================================
Parameter pack expansions
================================================================================

container<A,B,C...> t1;
container<C...,A,B> t2;

typedef Tuple<Pair<Args1, Args2>...> type;

f(&args...); // expands to f(&E1, &E2, &E3)
f(n, ++args...); // expands to f(n, ++E1, ++E2, ++E3);
f(++args..., n); // expands to f(++E1, ++E2, ++E3, n);
f(const_cast<const Args*>(&args)...); // f(const_cast<const E1*>(&X1), const_cast<const E2*>(&X2), const_cast<const E3*>(&X3))
f(h(args...) + args...); // expands to f(h(E1,E2,E3) + E1, h(E1,E2,E3) + E2, h(E1,E2,E3) + E3)

const int size = sizeof...(args) + 2;
int res[size] = {1,args...,2};
int dummy[sizeof...(Ts)] = { (std::cout << args, 0)... };

auto lm = [&, args...] { return g(args...); };

class X : public Mixins... {
public:
    X(const Mixins&... mixins) : Mixins(mixins)... { }
};

template <typename... Args>
void wrap(Args&&... args) {
    f(forward<Args>(args)...);
}

void f(T...) {}

--------------------------------------------------------------------------------

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        right: (number_literal))))
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  (class_specifier
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    (base_class_clause
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    body: (field_declaration_list
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              declarator: (reference_declarator
                (variadic_declarator
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        (field_initializer_list
          (field_initializer
            (field_identifier)
            (argument_list
              (identifier))))
        body: (compound_statement))))
  (template_declaration
    parameters: (template_parameter_list
      (variadic_type_parameter_declaration
        (type_identifier)))
    (function_definition
      type: (primitive_type)
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        declarator: (identifier)
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  (function_definition
    type: (primitive_type)
    declarator: (function_declarator
      declarator: (identifier)
      parameters: (parameter_list
        (variadic_parameter_declaration
          type: (type_identifier)
          declarator: (variadic_declarator))))
    body: (compound_statement)))

================================================================================
Concatenated string literals
================================================================================

"a" "b" "c";
R"(a)" R"(b)" R"(c)";
"a" R"(b)" L"c" R"FOO(d)FOO";
--------------------------------------------------------------------------------

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      (string_literal
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      (string_literal
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      (raw_string_literal
        (raw_string_content))
      (raw_string_literal
        (raw_string_content))))
  (expression_statement
    (concatenated_string
      (string_literal
        (string_content))
      (raw_string_literal
        (raw_string_content))
      (string_literal
        (string_content))
      (raw_string_literal
        (raw_string_delimiter)
        (raw_string_content)
        (raw_string_delimiter)))))

================================================================================
User-defined literals
================================================================================

1.2_km;
"foo" "bar"_baz;
--------------------------------------------------------------------------------

(translation_unit
  (expression_statement
    (user_defined_literal
      (number_literal)
      (literal_suffix)))
  (expression_statement
    (user_defined_literal
      (concatenated_string
        (string_literal
          (string_content))
        (string_literal
          (string_content)))
      (literal_suffix))))

================================================================================
Primitive types ctor
================================================================================

x = int(1);
x = new int(1);
x = (int(1) + float(2));

--------------------------------------------------------------------------------

(translation_unit
  (expression_statement
    (assignment_expression
      (identifier)
      (call_expression
        (primitive_type)
        (argument_list
          (number_literal)))))
  (expression_statement
    (assignment_expression
      (identifier)
      (new_expression
        (primitive_type)
        (argument_list
          (number_literal)))))
  (expression_statement
    (assignment_expression
      (identifier)
      (parenthesized_expression
        (binary_expression
          (call_expression
            (primitive_type)
            (argument_list
              (number_literal)))
          (call_expression
            (primitive_type)
            (argument_list
              (number_literal))))))))

================================================================================
Array assignment expression
================================================================================

array_[i] = s[i];
array_[{i}] = s[{1,2,3}];

--------------------------------------------------------------------------------

(translation_unit
  (expression_statement
    (assignment_expression
      (subscript_expression
        (identifier)
        (identifier))
      (subscript_expression
        (identifier)
        (identifier))))
  (expression_statement
    (assignment_expression
      (subscript_expression
        (identifier)
        (initializer_list
          (identifier)))
      (subscript_expression
        (identifier)
        (initializer_list
          (number_literal)
          (number_literal)
          (number_literal))))))

================================================================================
Coroutines
================================================================================

co_await fn();
co_await var;

--------------------------------------------------------------------------------

(translation_unit
  (expression_statement
    (co_await_expression
      (call_expression
        (identifier)
        (argument_list))))
  (expression_statement
    (co_await_expression
      (identifier))))

================================================================================
Three-way comparison
================================================================================

auto x = a <=> b;

bool y = 0 > a <=> b;

--------------------------------------------------------------------------------

(translation_unit
  (declaration
    (placeholder_type_specifier
      (auto))
    (init_declarator
      (identifier)
      (binary_expression
        (identifier)
        (identifier))))
  (declaration
    (primitive_type)
    (init_declarator
      (identifier)
      (binary_expression
        (number_literal)
        (binary_expression
          (identifier)
          (identifier))))))

================================================================================
Fold Expressions
================================================================================

bool t  = (... + IndexOf<T>);
bool t2 = (IndexOf<T> + ...);
bool t3 = (1 + ... + IndexOf<T>);
bool t3 = (IndexOf<T> + ... + 1);

--------------------------------------------------------------------------------

(translation_unit
  (declaration
    (primitive_type)
    (init_declarator
      (identifier)
      (fold_expression
        (template_function
          (identifier)
          (template_argument_list
            (type_descriptor
              (type_identifier)))))))
  (declaration
    (primitive_type)
    (init_declarator
      (identifier)
      (fold_expression
        (template_function
          (identifier)
          (template_argument_list
            (type_descriptor
              (type_identifier)))))))
  (declaration
    (primitive_type)
    (init_declarator
      (identifier)
      (fold_expression
        (number_literal)
        (template_function
          (identifier)
          (template_argument_list
            (type_descriptor
              (type_identifier)))))))
  (declaration
    (primitive_type)
    (init_declarator
      (identifier)
      (fold_expression
        (template_function
          (identifier)
          (template_argument_list
            (type_descriptor
              (type_identifier))))
        (number_literal)))))

================================================================================
Alternative tokens (digraphs)
================================================================================

if (not marked and (x < left or right < x)) {}

operator not_eq(int) { return true; }

foo and_eq bar();

--------------------------------------------------------------------------------

(translation_unit
  (if_statement
    (condition_clause
      (binary_expression
        (unary_expression
          (identifier))
        (parenthesized_expression
          (binary_expression
            (binary_expression
              (identifier)
              (identifier))
            (binary_expression
              (identifier)
              (identifier))))))
    (compound_statement))
  (function_definition
    (function_declarator
      (operator_name)
      (parameter_list
        (parameter_declaration
          (primitive_type))))
    (compound_statement
      (return_statement
        (true))))
  (expression_statement
    (assignment_expression
      (identifier)
      (call_expression
        (identifier)
        (argument_list)))))