Binder Symbolflags

    export const enum SymbolFlags {
        None                    = 0,
        FunctionScopedVariable  = 1 << 0,   // Variable (var) or parameter
        BlockScopedVariable     = 1 << 1,   // A block-scoped variable (let or const)
        Property                = 1 << 2,   // Property or enum member
        EnumMember              = 1 << 3,   // Enum member
        Function                = 1 << 4,   // Function
        Class                   = 1 << 5,   // Class
        Interface               = 1 << 6,   // Interface
        ConstEnum               = 1 << 7,   // Const enum
        RegularEnum             = 1 << 8,   // Enum
        ValueModule             = 1 << 9,   // Instantiated module
        NamespaceModule         = 1 << 10,  // Uninstantiated module
        TypeLiteral             = 1 << 11,  // Type Literal or mapped type
        ObjectLiteral           = 1 << 12,  // Object Literal
        Method                  = 1 << 13,  // Method
        Constructor             = 1 << 14,  // Constructor
        GetAccessor             = 1 << 15,  // Get accessor
        SetAccessor             = 1 << 16,  // Set accessor
        Signature               = 1 << 17,  // Call, construct, or index signature
        TypeParameter           = 1 << 18,  // Type parameter
        TypeAlias               = 1 << 19,  // Type alias
        ExportValue             = 1 << 20,  // Exported value marker (see comment in declareModuleMember in binder)
        ExportType              = 1 << 21,  // Exported type marker (see comment in declareModuleMember in binder)
        ExportNamespace         = 1 << 22,  // Exported namespace marker (see comment in declareModuleMember in binder)
        Alias                   = 1 << 23,  // An alias for another symbol (see comment in isAliasSymbolDeclaration in checker)
        Prototype               = 1 << 24,  // Prototype property (no source representation)
        ExportStar              = 1 << 25,  // Export * declaration
        Optional                = 1 << 26,  // Optional property
        Transient               = 1 << 27,  // Transient symbol (created during type check)

        Enum = RegularEnum | ConstEnum,
        Variable = FunctionScopedVariable | BlockScopedVariable,
        Value = Variable | Property | EnumMember | Function | Class | Enum | ValueModule | Method | GetAccessor | SetAccessor,
        Type = Class | Interface | Enum | EnumMember | TypeLiteral | ObjectLiteral | TypeParameter | TypeAlias,
        Namespace = ValueModule | NamespaceModule | Enum,
        Module = ValueModule | NamespaceModule,
        Accessor = GetAccessor | SetAccessor,

        // Variables can be redeclared, but can not redeclare a block-scoped declaration with the
        // same name, or any other value that is not a variable, e.g. ValueModule or Class
        FunctionScopedVariableExcludes = Value & ~FunctionScopedVariable,

        // Block-scoped declarations are not allowed to be re-declared
        // they can not merge with anything in the value space
        BlockScopedVariableExcludes = Value,

        ParameterExcludes = Value,
        PropertyExcludes = None,
        EnumMemberExcludes = Value | Type,
        FunctionExcludes = Value & ~(Function | ValueModule),
        ClassExcludes = (Value | Type) & ~(ValueModule | Interface), // class-interface mergability done in checker.ts
        InterfaceExcludes = Type & ~(Interface | Class),
        RegularEnumExcludes = (Value | Type) & ~(RegularEnum | ValueModule), // regular enums merge only with regular enums and modules
        ConstEnumExcludes = (Value | Type) & ~ConstEnum, // const enums merge only with const enums
        ValueModuleExcludes = Value & ~(Function | Class | RegularEnum | ValueModule),
        NamespaceModuleExcludes = 0,
        MethodExcludes = Value & ~Method,
        GetAccessorExcludes = Value & ~SetAccessor,
        SetAccessorExcludes = Value & ~GetAccessor,
        TypeParameterExcludes = Type & ~TypeParameter,
        TypeAliasExcludes = Type,
        AliasExcludes = Alias,

        ModuleMember = Variable | Function | Class | Interface | Enum | Module | TypeAlias | Alias,

        ExportHasLocal = Function | Class | Enum | ValueModule,

        HasExports = Class | Enum | Module,
        HasMembers = Class | Interface | TypeLiteral | ObjectLiteral,

        BlockScoped = BlockScopedVariable | Class | Enum,

        PropertyOrAccessor = Property | Accessor,
        Export = ExportNamespace | ExportType | ExportValue,

        ClassMember = Method | Accessor | Property,

        /* @internal */
        // The set of things we consider semantically classifiable.  Used to speed up the LS during
        // classification.
        Classifiable = Class | Enum | TypeAlias | Interface | TypeParameter | Module,
    }