Problems reported:

parser/error_recovery/issue_48411_prime_1:4:16: Expected '(' before this.
  C() : assert = 0;
               ^

parser/error_recovery/issue_48411_prime_1:4:16: Only factory constructor can specify '=' redirection.
  C() : assert = 0;
               ^

parser/error_recovery/issue_48411_prime_1:4:18: Expected an identifier, but got '0'.
  C() : assert = 0;
                 ^

parser/error_recovery/issue_48411_prime_1:4:16: Expected ';' after this.
  C() : assert = 0;
               ^

parser/error_recovery/issue_48411_prime_1:4:18: Expected a class member, but got '0'.
  C() : assert = 0;
                 ^

parser/error_recovery/issue_48411_prime_1:4:19: Expected a class member, but got ';'.
  C() : assert = 0;
                  ^

parser/error_recovery/issue_48411_prime_1:8:7: Expected an initializer.
  C() : null = 0;
      ^

parser/error_recovery/issue_48411_prime_1:8:9: Expected a function body, but got 'null'.
  C() : null = 0;
        ^^^^

parser/error_recovery/issue_48411_prime_1:8:9: Expected a class member, but got 'null'.
  C() : null = 0;
        ^^^^

parser/error_recovery/issue_48411_prime_1:8:14: Operator declarations must be preceded by the keyword 'operator'.
  C() : null = 0;
             ^

parser/error_recovery/issue_48411_prime_1:8:14: The string '=' isn't a user-definable operator.
  C() : null = 0;
             ^

parser/error_recovery/issue_48411_prime_1:8:14: A method declaration needs an explicit list of parameters.
  C() : null = 0;
             ^

parser/error_recovery/issue_48411_prime_1:8:16: Expected a function body, but got '0'.
  C() : null = 0;
               ^

parser/error_recovery/issue_48411_prime_1:8:16: Expected a class member, but got '0'.
  C() : null = 0;
               ^

parser/error_recovery/issue_48411_prime_1:8:17: Expected a class member, but got ';'.
  C() : null = 0;
                ^

parser/error_recovery/issue_48411_prime_1:16:14: Expected '.' before this.
  C() : this = 0;
             ^

parser/error_recovery/issue_48411_prime_1:16:9: Expected an assignment after the field name.
  C() : this = 0;
        ^^^^

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    handleIdentifier(C, classOrMixinDeclaration)
    handleNoTypeVariables({)
    beginClassDeclaration(class, null, null, null, C)
      handleNoType(C)
      handleClassExtends(null, 1)
      handleClassNoWithClause()
      handleImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
        beginMetadataStar(C)
        endMetadataStar(0)
        beginMember()
          beginMethod(DeclarationKind.Class, null, null, null, null, null, C)
            handleNoType({)
            handleIdentifier(C, methodDeclaration)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            beginInitializers(:)
              beginInitializer(assert)
                beginAssert(assert, Assert.Initializer)
                  handleRecoverableError(Message[ExpectedButGot, Expected '(' before this., null, {string: (}], =, =)
                  handleIdentifier(, expression)
                  handleNoTypeArguments())
                  handleNoArguments())
                  handleSend(, ))
                endAssert(assert, Assert.Initializer, (, null, =)
              endInitializer(=)
            endInitializers(1, :, =)
            handleAsyncModifier(null, null)
            handleRecoverableError(RedirectionInNonFactory, =, =)
            beginRedirectingFactoryBody(=)
              handleRecoverableError(Message[ExpectedIdentifier, Expected an identifier, but got '0'., Try inserting an identifier before '0'., {lexeme: 0}], 0, 0)
              handleIdentifier(, constructorReference)
              beginConstructorReference()
                handleNoTypeArguments(0)
                handleNoConstructorReferenceContinuationAfterTypeArguments(0)
              endConstructorReference(, null, 0, ConstructorReferenceContext.RedirectingFactory)
              handleRecoverableError(Message[ExpectedAfterButGot, Expected ';' after this., null, {string: ;}], =, =)
            endRedirectingFactoryBody(=, ;)
          endClassConstructor(null, C, (, :, ;)
        endMember()
        beginMetadataStar(0)
        endMetadataStar(0)
        beginMember()
          handleRecoverableError(Message[ExpectedClassMember, Expected a class member, but got '0'., null, {lexeme: 0}], 0, 0)
          handleInvalidMember(0)
        endMember()
        beginMetadataStar(;)
        endMetadataStar(0)
        beginMember()
          handleRecoverableError(Message[ExpectedClassMember, Expected a class member, but got ';'., null, {lexeme: ;}], ;, ;)
          handleInvalidMember(;)
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      handleNoType(C)
      handleClassExtends(null, 1)
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      handleImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
        beginMetadataStar(C)
        endMetadataStar(0)
        beginMember()
          beginMethod(DeclarationKind.Class, null, null, null, null, null, C)
            handleNoType({)
            handleIdentifier(C, methodDeclaration)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            beginInitializers(:)
              beginInitializer(null)
                handleRecoverableError(ExpectedAnInitializer, :, :)
                handleIdentifier(, expression)
                handleNoTypeArguments(=)
                handleNoArguments(=)
                handleSend(, =)
                handleIdentifier(, expression)
                handleNoTypeArguments(null)
                handleNoArguments(null)
                handleSend(, null)
                handleAssignmentExpression(=)
              endInitializer(null)
            endInitializers(1, :, null)
            handleAsyncModifier(null, null)
            handleRecoverableError(Message[ExpectedFunctionBody, Expected a function body, but got 'null'., null, {lexeme: null}], null, null)
            handleInvalidFunctionBody({)
          endClassConstructor(null, C, (, :, })
        endMember()
        beginMetadataStar(null)
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        beginMember()
          handleRecoverableError(Message[ExpectedClassMember, Expected a class member, but got 'null'., null, {lexeme: null}], null, null)
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        beginMetadataStar(=)
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        beginMember()
          handleRecoverableError(MissingOperatorKeyword, =, =)
          beginMethod(DeclarationKind.Class, null, null, null, null, null, operator)
            handleNoType(null)
            handleRecoverableError(Message[InvalidOperator, The string '=' isn't a user-definable operator., null, {lexeme: =}], =, =)
            handleInvalidOperatorName(operator, =)
            handleNoTypeVariables(0)
            handleRecoverableError(MissingMethodParameters, =, =)
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            handleNoInitializers()
            handleAsyncModifier(null, null)
            handleRecoverableError(Message[ExpectedFunctionBody, Expected a function body, but got '0'., null, {lexeme: 0}], 0, 0)
            handleInvalidFunctionBody({)
          endClassMethod(null, operator, (, null, })
        endMember()
        beginMetadataStar(0)
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        beginMember()
          handleRecoverableError(Message[ExpectedClassMember, Expected a class member, but got '0'., null, {lexeme: 0}], 0, 0)
          handleInvalidMember(0)
        endMember()
        beginMetadataStar(;)
        endMetadataStar(0)
        beginMember()
          handleRecoverableError(Message[ExpectedClassMember, Expected a class member, but got ';'., null, {lexeme: ;}], ;, ;)
          handleInvalidMember(;)
        endMember()
      endClassOrMixinOrExtensionBody(DeclarationKind.Class, 5, {, })
    endClassDeclaration(class, })
  endTopLevelDeclaration(class)
  beginMetadataStar(class)
  endMetadataStar(0)
  beginClassOrMixinOrNamedMixinApplicationPrelude(class)
    handleIdentifier(C, classOrMixinDeclaration)
    handleNoTypeVariables({)
    beginClassDeclaration(class, null, null, null, C)
      handleNoType(C)
      handleClassExtends(null, 1)
      handleClassNoWithClause()
      handleImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
        beginMetadataStar(C)
        endMetadataStar(0)
        beginMember()
          beginMethod(DeclarationKind.Class, null, null, null, null, null, C)
            handleNoType({)
            handleIdentifier(C, methodDeclaration)
            handleNoTypeVariables(()
            beginFormalParameters((, MemberKind.NonStaticMethod)
            endFormalParameters(0, (, ), MemberKind.NonStaticMethod)
            beginInitializers(:)
              beginInitializer(super)
                handleSuperExpression(super, expression)
                handleLiteralInt(0)
                handleAssignmentExpression(=)
              endInitializer(;)
            endInitializers(1, :, ;)
            handleAsyncModifier(null, null)
            handleEmptyFunctionBody(;)
          endClassConstructor(null, C, (, :, ;)
        endMember()
      endClassOrMixinOrExtensionBody(DeclarationKind.Class, 1, {, })
    endClassDeclaration(class, })
  endTopLevelDeclaration(class)
  beginMetadataStar(class)
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  beginClassOrMixinOrNamedMixinApplicationPrelude(class)
    handleIdentifier(C, classOrMixinDeclaration)
    handleNoTypeVariables({)
    beginClassDeclaration(class, null, null, null, C)
      handleNoType(C)
      handleClassExtends(null, 1)
      handleClassNoWithClause()
      handleImplements(null, 0)
      handleClassHeader(class, class, null)
      beginClassOrMixinOrExtensionBody(DeclarationKind.Class, {)
        beginMetadataStar(C)
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        beginMember()
          beginMethod(DeclarationKind.Class, null, null, null, null, null, C)
            handleNoType({)
            handleIdentifier(C, methodDeclaration)
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            beginInitializers(:)
              beginInitializer(this)
                handleRecoverableError(Message[ExpectedButGot, Expected '.' before this., null, {string: .}], =, =)
                handleRecoverableError(MissingAssignmentInInitializer, this, this)
                handleIdentifier(, expression)
                handleNoTypeArguments(=)
                handleNoArguments(=)
                handleSend(, =)
                handleThisExpression(this, expression)
                handleIdentifier(, expressionContinuation)
                handleNoTypeArguments(=)
                handleNoArguments(=)
                handleSend(, =)
                handleEndingBinaryExpression(.)
                handleLiteralInt(0)
                handleAssignmentExpression(=)
                handleAssignmentExpression(=)
              endInitializer(;)
            endInitializers(1, :, ;)
            handleAsyncModifier(null, null)
            handleEmptyFunctionBody(;)
          endClassConstructor(null, C, (, :, ;)
        endMember()
      endClassOrMixinOrExtensionBody(DeclarationKind.Class, 1, {, })
    endClassDeclaration(class, })
  endTopLevelDeclaration()
endCompilationUnit(4, )