path: root/gcc/rust/parse/rust-parse.h

#ifndef RUST_PARSE_H
#define RUST_PARSE_H

#include "rust-lex.h"
#include "rust-ast-full.h"

namespace Rust {
/* HACK: used to resolve the expression-or-statement problem at the end of a
 * block by allowing either to be returned (technically). Tagged union would
 * probably take up the same amount of space. */
struct ExprOrStmt
{
  ::std::unique_ptr<AST::ExprWithoutBlock> expr;
  ::std::unique_ptr<AST::Stmt> stmt;

  /* I was going to resist the urge to make this a real class and make it POD,
   * but construction in steps is too difficult. So it'll just also have a
   * constructor. */

  // expression constructor
  ExprOrStmt (::std::unique_ptr<AST::ExprWithoutBlock> expr)
    : expr (::std::move (expr))
  {}

  // statement constructor
  ExprOrStmt (::std::unique_ptr<AST::Stmt> stmt) : stmt (::std::move (stmt)) {}

  // Returns whether this object is in an error state.
  inline bool is_error () const
  {
    return (expr == NULL && stmt == NULL) || (expr != NULL && stmt != NULL);
  }

  // Returns an error state object.
  static ExprOrStmt create_error () { return ExprOrStmt (NULL, NULL); }

  ~ExprOrStmt () = default;

  // no copy constructors/assignment copy as simple object like this shouldn't
  // require it

  // move constructors
  ExprOrStmt (ExprOrStmt &&other) = default;
  ExprOrStmt &operator= (ExprOrStmt &&other) = default;

private:
  // private constructor only used for creating error state expr or stmt objects
  ExprOrStmt (AST::ExprWithoutBlock *expr, AST::Stmt *stmt)
    : expr (expr), stmt (stmt)
  {}

  // make this work: have a disambiguation specifically for known statements
  // (i.e. ';' and 'let'). then, have a special "parse expr or stmt" function
  // that returns this type. inside it, it parses an expression, and then
  // determines whether to return expr or stmt via whether the next token is a
  // semicolon. should be able to disambiguate inside that function between
  // stmts with blocks and without blocks.
};

/* Restrictions on parsing used to signal that certain ambiguous grammar
 * features should be parsed in a certain way.*/
struct ParseRestrictions
{
  bool can_be_struct_expr = true;
  /* Whether the expression was entered from a unary expression - prevents stuff
   * like struct exprs being parsed from a dereference. */
  bool entered_from_unary = false;
};

// Parser implementation for gccrs.
class Parser
{
private:
  void skip_after_semicolon ();
  void skip_after_end ();
  void skip_after_end_block ();
  void skip_after_next_block ();
  void skip_after_end_attribute ();

  bool skip_token (TokenId t);
  const_TokenPtr expect_token (TokenId t);
  void unexpected_token (const_TokenPtr t);
  bool skip_generics_right_angle ();

  void parse_statement_seq (bool (Parser::*done) ());

  // AST-related stuff - maybe move or something?
  ::std::vector<AST::Attribute> parse_inner_attributes ();
  AST::Attribute parse_inner_attribute ();
  ::std::vector<AST::Attribute> parse_outer_attributes ();
  AST::Attribute parse_outer_attribute ();
  AST::Attribute parse_attribute_body ();
  ::std::unique_ptr<AST::AttrInput> parse_attr_input ();

  // Path-related
  AST::SimplePath parse_simple_path ();
  AST::SimplePathSegment parse_simple_path_segment ();
  AST::TypePath parse_type_path ();
  ::std::unique_ptr<AST::TypePathSegment> parse_type_path_segment ();
  AST::PathIdentSegment parse_path_ident_segment ();
  AST::GenericArgs parse_path_generic_args ();
  AST::GenericArgsBinding parse_generic_args_binding ();
  AST::TypePathFunction parse_type_path_function ();
  AST::PathInExpression parse_path_in_expression ();
  AST::PathExprSegment parse_path_expr_segment ();
  AST::QualifiedPathInExpression
  parse_qualified_path_in_expression (bool pratt_parse = false);
  AST::QualifiedPathType parse_qualified_path_type (bool pratt_parse = false);
  AST::QualifiedPathInType parse_qualified_path_in_type ();

  // Token tree or macro related
  AST::DelimTokenTree parse_delim_token_tree ();
  ::std::unique_ptr<AST::TokenTree> parse_token_tree ();
  ::std::unique_ptr<AST::MacroRulesDefinition>
  parse_macro_rules_def (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::MacroInvocationSemi>
  parse_macro_invocation_semi (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::MacroInvocation>
  parse_macro_invocation (::std::vector<AST::Attribute> outer_attrs);
  AST::MacroRule parse_macro_rule ();
  AST::MacroMatcher parse_macro_matcher ();
  ::std::unique_ptr<AST::MacroMatch> parse_macro_match ();
  ::std::unique_ptr<AST::MacroMatchFragment> parse_macro_match_fragment ();
  ::std::unique_ptr<AST::MacroMatchRepetition> parse_macro_match_repetition ();

  // Top-level item-related
  ::std::vector< ::std::unique_ptr<AST::Item> > parse_items ();
  ::std::unique_ptr<AST::Item> parse_item (bool called_from_statement);
  ::std::unique_ptr<AST::VisItem>
  parse_vis_item (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::MacroItem>
  parse_macro_item (::std::vector<AST::Attribute> outer_attrs);
  AST::Visibility parse_visibility ();

  // VisItem subclass-related
  ::std::unique_ptr<AST::Module>
  parse_module (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExternCrate>
  parse_extern_crate (AST::Visibility vis,
		      ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::UseDeclaration>
  parse_use_decl (AST::Visibility vis,
		  ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::UseTree> parse_use_tree ();
  ::std::unique_ptr<AST::Function>
  parse_function (AST::Visibility vis,
		  ::std::vector<AST::Attribute> outer_attrs);
  AST::FunctionQualifiers parse_function_qualifiers ();
  ::std::vector< ::std::unique_ptr<AST::GenericParam> >
  parse_generic_params_in_angles ();
  ::std::vector< ::std::unique_ptr<AST::GenericParam> > parse_generic_params ();
  ::std::vector< ::std::unique_ptr<AST::LifetimeParam> >
  parse_lifetime_params ();
  ::std::vector<AST::LifetimeParam> parse_lifetime_params_objs ();
  AST::LifetimeParam parse_lifetime_param ();
  ::std::vector< ::std::unique_ptr<AST::TypeParam> > parse_type_params ();
  ::std::unique_ptr<AST::TypeParam> parse_type_param ();
  ::std::vector<AST::FunctionParam> parse_function_params ();
  AST::FunctionParam parse_function_param ();
  ::std::unique_ptr<AST::Type> parse_function_return_type ();
  AST::WhereClause parse_where_clause ();
  ::std::unique_ptr<AST::WhereClauseItem> parse_where_clause_item ();
  ::std::unique_ptr<AST::LifetimeWhereClauseItem>
  parse_lifetime_where_clause_item ();
  ::std::unique_ptr<AST::TypeBoundWhereClauseItem>
  parse_type_bound_where_clause_item ();
  ::std::vector<AST::LifetimeParam> parse_for_lifetimes ();
  ::std::vector< ::std::unique_ptr<AST::TypeParamBound> >
  parse_type_param_bounds ();
  ::std::unique_ptr<AST::TypeParamBound> parse_type_param_bound ();
  ::std::unique_ptr<AST::TraitBound> parse_trait_bound ();
  ::std::vector<AST::Lifetime> parse_lifetime_bounds ();
  AST::Lifetime parse_lifetime ();
  ::std::unique_ptr<AST::TypeAlias>
  parse_type_alias (AST::Visibility vis,
		    ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::Struct>
  parse_struct (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::vector<AST::StructField> parse_struct_fields ();
  AST::StructField parse_struct_field ();
  ::std::vector<AST::TupleField> parse_tuple_fields ();
  AST::TupleField parse_tuple_field ();
  ::std::unique_ptr<AST::Enum>
  parse_enum (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::vector< ::std::unique_ptr<AST::EnumItem> > parse_enum_items ();
  ::std::unique_ptr<AST::EnumItem> parse_enum_item ();
  ::std::unique_ptr<AST::Union>
  parse_union (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ConstantItem>
  parse_const_item (AST::Visibility vis,
		    ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::StaticItem>
  parse_static_item (AST::Visibility vis,
		     ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::Trait>
  parse_trait (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::TraitItem> parse_trait_item ();
  ::std::unique_ptr<AST::TraitItemType>
  parse_trait_type (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::TraitItemConst>
  parse_trait_const (::std::vector<AST::Attribute> outer_attrs);
  AST::SelfParam parse_self_param ();
  ::std::unique_ptr<AST::Impl>
  parse_impl (AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::InherentImplItem> parse_inherent_impl_item ();
  ::std::unique_ptr<AST::InherentImplItem>
  parse_inherent_impl_function_or_method (
    AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::TraitImplItem> parse_trait_impl_item ();
  ::std::unique_ptr<AST::TraitImplItem> parse_trait_impl_function_or_method (
    AST::Visibility vis, ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExternBlock>
  parse_extern_block (AST::Visibility vis,
		      ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExternalItem> parse_external_item ();
  AST::NamedFunctionParam parse_named_function_param ();
  AST::Method parse_method ();

  // Expression-related (Pratt parsed)
  ::std::unique_ptr<AST::Expr>
  parse_expr (::std::vector<AST::Attribute> outer_attrs
	      = ::std::vector<AST::Attribute> (),
	      ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::Expr>
  parse_expr (int right_binding_power,
	      ::std::vector<AST::Attribute> outer_attrs
	      = ::std::vector<AST::Attribute> (),
	      ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::Expr>
  null_denotation_NEW (const_TokenPtr t,
		       ::std::vector<AST::Attribute> outer_attrs
		       = ::std::vector<AST::Attribute> (),
		       ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::Expr>
  left_denotation (const_TokenPtr t, ::std::unique_ptr<AST::Expr> left,
		   ::std::vector<AST::Attribute> outer_attrs
		   = ::std::vector<AST::Attribute> (),
		   ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_binary_plus_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr> parse_binary_minus_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_binary_mult_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_binary_div_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_binary_mod_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_bitwise_and_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_bitwise_or_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_bitwise_xor_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_left_shift_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArithmeticOrLogicalExpr>
  parse_right_shift_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_equal_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_not_equal_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_greater_than_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_less_than_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_greater_equal_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ComparisonExpr> parse_binary_less_equal_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::LazyBooleanExpr>
  parse_lazy_or_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
		      ::std::vector<AST::Attribute> outer_attrs,
		      ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::LazyBooleanExpr>
  parse_lazy_and_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
		       ::std::vector<AST::Attribute> outer_attrs,
		       ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::TypeCastExpr>
  parse_type_cast_expr (const_TokenPtr tok,
			::std::unique_ptr<AST::Expr> expr_to_cast,
			::std::vector<AST::Attribute> outer_attrs,
			ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::AssignmentExpr>
  parse_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
		    ::std::vector<AST::Attribute> outer_attrs,
		    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_plus_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_minus_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			  ::std::vector<AST::Attribute> outer_attrs,
			  ParseRestrictions restrictions
			  = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_mult_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			 ::std::vector<AST::Attribute> outer_attrs,
			 ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_div_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			::std::vector<AST::Attribute> outer_attrs,
			ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_mod_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			::std::vector<AST::Attribute> outer_attrs,
			ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_and_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			::std::vector<AST::Attribute> outer_attrs,
			ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_or_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
		       ::std::vector<AST::Attribute> outer_attrs,
		       ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr>
  parse_xor_assig_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
			::std::vector<AST::Attribute> outer_attrs,
			ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr> parse_left_shift_assig_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CompoundAssignmentExpr> parse_right_shift_assig_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::AwaitExpr>
  parse_await_expr (const_TokenPtr tok,
		    ::std::unique_ptr<AST::Expr> expr_to_await,
		    ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::MethodCallExpr> parse_method_call_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> receiver_expr,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::CallExpr> parse_function_call_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> function_expr,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::RangeExpr> parse_led_range_exclusive_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::RangeExpr>
  parse_nud_range_exclusive_expr (const_TokenPtr tok,
				  ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::RangeFromToInclExpr> parse_range_inclusive_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> left,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::RangeToInclExpr>
  parse_range_to_inclusive_expr (const_TokenPtr tok,
				 ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::TupleIndexExpr> parse_tuple_index_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> tuple_expr,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::FieldAccessExpr> parse_field_access_expr (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> struct_expr,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::ArrayIndexExpr>
  parse_index_expr (const_TokenPtr tok, ::std::unique_ptr<AST::Expr> array_expr,
		    ::std::vector<AST::Attribute> outer_attrs,
		    ParseRestrictions restrictions = ParseRestrictions ());
  ::std::unique_ptr<AST::MacroInvocation>
  parse_macro_invocation_partial (AST::PathInExpression path,
				  ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::StructExprStruct>
  parse_struct_expr_struct_partial (AST::PathInExpression path,
				    ::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::CallExpr>
  parse_struct_expr_tuple_partial (AST::PathInExpression path,
				   ::std::vector<AST::Attribute> outer_attrs);
  AST::PathInExpression parse_path_in_expression_pratt (const_TokenPtr tok);
  ::std::unique_ptr<AST::ClosureExpr>
  parse_closure_expr_pratt (const_TokenPtr tok,
			    ::std::vector<AST::Attribute> outer_attrs
			    = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::TupleIndexExpr> parse_tuple_index_expr_float (
    const_TokenPtr tok, ::std::unique_ptr<AST::Expr> tuple_expr,
    ::std::vector<AST::Attribute> outer_attrs,
    ParseRestrictions restrictions = ParseRestrictions ());

  // Expression-related (non-Pratt parsed)
  ::std::unique_ptr<AST::ExprWithoutBlock>
  parse_expr_without_block (::std::vector<AST::Attribute> outer_attrs
			    = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::BlockExpr>
  parse_block_expr (::std::vector<AST::Attribute> outer_attrs
		    = ::std::vector<AST::Attribute> (),
		    bool pratt_parse = false);
  ::std::unique_ptr<AST::IfExpr>
  parse_if_expr (::std::vector<AST::Attribute> outer_attrs
		 = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::IfLetExpr>
  parse_if_let_expr (::std::vector<AST::Attribute> outer_attrs
		     = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::LoopExpr>
  parse_loop_expr (::std::vector<AST::Attribute> outer_attrs
		   = ::std::vector<AST::Attribute> (),
		   AST::LoopLabel label = AST::LoopLabel::error ());
  ::std::unique_ptr<AST::WhileLoopExpr>
  parse_while_loop_expr (::std::vector<AST::Attribute> outer_attrs
			 = ::std::vector<AST::Attribute> (),
			 AST::LoopLabel label = AST::LoopLabel::error ());
  ::std::unique_ptr<AST::WhileLetLoopExpr>
  parse_while_let_loop_expr (::std::vector<AST::Attribute> outer_attrs
			     = ::std::vector<AST::Attribute> (),
			     AST::LoopLabel label = AST::LoopLabel::error ());
  ::std::unique_ptr<AST::ForLoopExpr>
  parse_for_loop_expr (::std::vector<AST::Attribute> outer_attrs
		       = ::std::vector<AST::Attribute> (),
		       AST::LoopLabel label = AST::LoopLabel::error ());
  ::std::unique_ptr<AST::MatchExpr>
  parse_match_expr (::std::vector<AST::Attribute> outer_attrs
		    = ::std::vector<AST::Attribute> (),
		    bool pratt_parse = false);
  AST::MatchArm parse_match_arm ();
  ::std::vector< ::std::unique_ptr<AST::Pattern> >
  parse_match_arm_patterns (TokenId end_token_id);
  ::std::unique_ptr<AST::BaseLoopExpr>
  parse_labelled_loop_expr (::std::vector<AST::Attribute> outer_attrs
			    = ::std::vector<AST::Attribute> ());
  AST::LoopLabel parse_loop_label ();
  ::std::unique_ptr<AST::AsyncBlockExpr>
  parse_async_block_expr (::std::vector<AST::Attribute> outer_attrs
			  = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::UnsafeBlockExpr>
  parse_unsafe_block_expr (::std::vector<AST::Attribute> outer_attrs
			   = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::GroupedExpr>
  parse_grouped_expr (::std::vector<AST::Attribute> outer_attrs
		      = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::ClosureExpr>
  parse_closure_expr (::std::vector<AST::Attribute> outer_attrs
		      = ::std::vector<AST::Attribute> ());
  AST::ClosureParam parse_closure_param ();
  ::std::unique_ptr<AST::LiteralExpr>
  parse_literal_expr (::std::vector<AST::Attribute> outer_attrs
		      = ::std::vector<AST::Attribute> ());
  ::std::unique_ptr<AST::ReturnExpr>
  parse_return_expr (::std::vector<AST::Attribute> outer_attrs
		     = ::std::vector<AST::Attribute> (),
		     bool pratt_parse = false);
  ::std::unique_ptr<AST::BreakExpr>
  parse_break_expr (::std::vector<AST::Attribute> outer_attrs
		    = ::std::vector<AST::Attribute> (),
		    bool pratt_parse = false);
  ::std::unique_ptr<AST::ContinueExpr>
  parse_continue_expr (::std::vector<AST::Attribute> outer_attrs
		       = ::std::vector<AST::Attribute> (),
		       bool pratt_parse = false);
  ::std::unique_ptr<AST::ArrayExpr>
  parse_array_expr (::std::vector<AST::Attribute> outer_attrs
		    = ::std::vector<AST::Attribute> (),
		    bool pratt_parse = false);
  ::std::unique_ptr<AST::ExprWithoutBlock>
  parse_grouped_or_tuple_expr (::std::vector<AST::Attribute> outer_attrs
			       = ::std::vector<AST::Attribute> (),
			       bool pratt_parse = false);
  ::std::unique_ptr<AST::StructExprField> parse_struct_expr_field ();

  // Type-related
  ::std::unique_ptr<AST::Type> parse_type ();
  ::std::unique_ptr<AST::TypeNoBounds> parse_type_no_bounds ();
  ::std::unique_ptr<AST::TypeNoBounds> parse_slice_or_array_type ();
  ::std::unique_ptr<AST::RawPointerType> parse_raw_pointer_type ();
  ::std::unique_ptr<AST::ReferenceType> parse_reference_type ();
  ::std::unique_ptr<AST::BareFunctionType>
  parse_bare_function_type (::std::vector<AST::LifetimeParam> for_lifetimes);
  ::std::unique_ptr<AST::Type> parse_paren_prefixed_type ();
  ::std::unique_ptr<AST::TypeNoBounds> parse_paren_prefixed_type_no_bounds ();
  ::std::unique_ptr<AST::Type> parse_for_prefixed_type ();
  AST::MaybeNamedParam parse_maybe_named_param ();

  // Statement-related
  ::std::unique_ptr<AST::Stmt> parse_stmt ();
  ::std::unique_ptr<AST::LetStmt>
  parse_let_stmt (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExprStmt>
  parse_expr_stmt (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExprStmtWithBlock>
  parse_expr_stmt_with_block (::std::vector<AST::Attribute> outer_attrs);
  ::std::unique_ptr<AST::ExprStmtWithoutBlock>
  parse_expr_stmt_without_block (::std::vector<AST::Attribute> outer_attrs);
  ExprOrStmt parse_stmt_or_expr_without_block ();
  ExprOrStmt
  parse_macro_invocation_maybe_semi (::std::vector<AST::Attribute> outer_attrs);
  ExprOrStmt
  parse_path_based_stmt_or_expr (::std::vector<AST::Attribute> outer_attrs);

  // Pattern-related
  ::std::unique_ptr<AST::Pattern> parse_pattern ();
  ::std::unique_ptr<AST::Pattern> parse_literal_or_range_pattern ();
  ::std::unique_ptr<AST::RangePatternBound> parse_range_pattern_bound ();
  ::std::unique_ptr<AST::ReferencePattern> parse_reference_pattern ();
  ::std::unique_ptr<AST::Pattern> parse_grouped_or_tuple_pattern ();
  ::std::unique_ptr<AST::SlicePattern> parse_slice_pattern ();
  ::std::unique_ptr<AST::IdentifierPattern> parse_identifier_pattern ();
  ::std::unique_ptr<AST::Pattern> parse_ident_leading_pattern ();
  ::std::unique_ptr<AST::TupleStructItems> parse_tuple_struct_items ();
  AST::StructPatternElements parse_struct_pattern_elems ();
  ::std::unique_ptr<AST::StructPatternField> parse_struct_pattern_field ();

  int left_binding_power (const_TokenPtr token);

  bool done_end ();
  bool done_end_or_else ();
  bool done_end_of_file ();

public:
  // Construct parser with specified lexer reference.
  Parser (Lexer &parLexer) : lexer (parLexer) {}

  // Main entry point for parser.
  AST::Crate parse_crate ();

  // Dumps all lexer output.
  void debug_dump_lex_output ();
  void debug_dump_ast_output (AST::Crate &crate);

private:
  // The lexer associated with the parser.
  Lexer &lexer;
};
} // namespace Rust

#endif // RUST_PARSE_H