What does the assert() indicate here?












2















Here is code snippet,



 function transfer(address _to, uint _value, bytes memory _data, string memory _custom_fallback) public returns (bool success) {



   if(isContract(_to)) {

       if (balanceOf(msg.sender) < _value) revert();

       balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);

       balances[_to] = safeAdd(balanceOf(_to), _value);

       assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));

       emit Transfer(msg.sender, _to, _value, _data);

    return true;

   }

   else {

       return transferToAddress(_to, _value, _data);

   }

}


I am currently working with Solidity Version ^0.5.1. What is the alternative and upgraded method to execute this assert function given below. And what is the main working of this assert() and their arguments?




assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));







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    2















    Here is code snippet,



     function transfer(address _to, uint _value, bytes memory _data, string memory _custom_fallback) public returns (bool success) {
    

    
   if(isContract(_to)) {
    
       if (balanceOf(msg.sender) < _value) revert();
    
       balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
    
       balances[_to] = safeAdd(balanceOf(_to), _value);
    
       assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));
    
       emit Transfer(msg.sender, _to, _value, _data);
    
    return true;
    
   }
    
   else {
    
       return transferToAddress(_to, _value, _data);
    
   }
    
}


    I am currently working with Solidity Version ^0.5.1. What is the alternative and upgraded method to execute this assert function given below. And what is the main working of this assert() and their arguments?




    assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));







    solidity remix erc-223







    share|improve this question



























      2












      2








      2








      Here is code snippet,



       function transfer(address _to, uint _value, bytes memory _data, string memory _custom_fallback) public returns (bool success) {
      

      
   if(isContract(_to)) {
      
       if (balanceOf(msg.sender) < _value) revert();
      
       balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
      
       balances[_to] = safeAdd(balanceOf(_to), _value);
      
       assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));
      
       emit Transfer(msg.sender, _to, _value, _data);
      
    return true;
      
   }
      
   else {
      
       return transferToAddress(_to, _value, _data);
      
   }
      
}


      I am currently working with Solidity Version ^0.5.1. What is the alternative and upgraded method to execute this assert function given below. And what is the main working of this assert() and their arguments?




      assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));







      solidity remix erc-223







      share|improve this question
















      Here is code snippet,



       function transfer(address _to, uint _value, bytes memory _data, string memory _custom_fallback) public returns (bool success) {
      

      
   if(isContract(_to)) {
      
       if (balanceOf(msg.sender) < _value) revert();
      
       balances[msg.sender] = safeSub(balanceOf(msg.sender), _value);
      
       balances[_to] = safeAdd(balanceOf(_to), _value);
      
       assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));
      
       emit Transfer(msg.sender, _to, _value, _data);
      
    return true;
      
   }
      
   else {
      
       return transferToAddress(_to, _value, _data);
      
   }
      
}


      I am currently working with Solidity Version ^0.5.1. What is the alternative and upgraded method to execute this assert function given below. And what is the main working of this assert() and their arguments?




      assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)), msg.sender, _value, _data));







      solidity remix erc-223




      solidity remix erc-223






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 39 mins ago









      Aniket

      2,1721733




      2,1721733










      asked 1 hour ago









      RudrikaRudrika

      749




      749






















          1 Answer
          1






          active

          oldest

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          2















          assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)),
          msg.sender, _value, _data));





          • what is the main working of this assert() and their arguments?


          This assert is calling a function of _to (when it is a contract) passed as a parameter in transfer and checking the return value as true. bytes4(keccak256(_custom_fallback)) is used to select the function to execute and msg.sender, _value, _data are the parameter values to pass in calling function. value(0) signifies the sending of 0 wei with the call.



          See related: Whats the difference between .call.value() and .call.value()()




          • What is the alternative and upgraded method to execute this assert
            function given below


          You can use abi.encodeWithSignature(string memory signature, ...) returns (bytes memory) as:




          _to.call.value(0)(abi.encodeWithSignature(_custom_fallback, msg.sender, _value, _data));




          See related: https://solidity.readthedocs.io/en/v0.5.3/units-and-global-variables.html#abi-encoding-and-decoding-functions






          share|improve this answer
























          • Thank you for the Answer...!

            – Rudrika
            13 mins ago











          • But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

            – Rudrika
            10 mins ago











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          1 Answer
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          1 Answer
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          active

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          2















          assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)),
          msg.sender, _value, _data));





          • what is the main working of this assert() and their arguments?


          This assert is calling a function of _to (when it is a contract) passed as a parameter in transfer and checking the return value as true. bytes4(keccak256(_custom_fallback)) is used to select the function to execute and msg.sender, _value, _data are the parameter values to pass in calling function. value(0) signifies the sending of 0 wei with the call.



          See related: Whats the difference between .call.value() and .call.value()()




          • What is the alternative and upgraded method to execute this assert
            function given below


          You can use abi.encodeWithSignature(string memory signature, ...) returns (bytes memory) as:




          _to.call.value(0)(abi.encodeWithSignature(_custom_fallback, msg.sender, _value, _data));




          See related: https://solidity.readthedocs.io/en/v0.5.3/units-and-global-variables.html#abi-encoding-and-decoding-functions






          share|improve this answer
























          • Thank you for the Answer...!

            – Rudrika
            13 mins ago











          • But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

            – Rudrika
            10 mins ago
















          2















          assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)),
          msg.sender, _value, _data));





          • what is the main working of this assert() and their arguments?


          This assert is calling a function of _to (when it is a contract) passed as a parameter in transfer and checking the return value as true. bytes4(keccak256(_custom_fallback)) is used to select the function to execute and msg.sender, _value, _data are the parameter values to pass in calling function. value(0) signifies the sending of 0 wei with the call.



          See related: Whats the difference between .call.value() and .call.value()()




          • What is the alternative and upgraded method to execute this assert
            function given below


          You can use abi.encodeWithSignature(string memory signature, ...) returns (bytes memory) as:




          _to.call.value(0)(abi.encodeWithSignature(_custom_fallback, msg.sender, _value, _data));




          See related: https://solidity.readthedocs.io/en/v0.5.3/units-and-global-variables.html#abi-encoding-and-decoding-functions






          share|improve this answer
























          • Thank you for the Answer...!

            – Rudrika
            13 mins ago











          • But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

            – Rudrika
            10 mins ago














          2












          2








          2








          assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)),
          msg.sender, _value, _data));





          • what is the main working of this assert() and their arguments?


          This assert is calling a function of _to (when it is a contract) passed as a parameter in transfer and checking the return value as true. bytes4(keccak256(_custom_fallback)) is used to select the function to execute and msg.sender, _value, _data are the parameter values to pass in calling function. value(0) signifies the sending of 0 wei with the call.



          See related: Whats the difference between .call.value() and .call.value()()




          • What is the alternative and upgraded method to execute this assert
            function given below


          You can use abi.encodeWithSignature(string memory signature, ...) returns (bytes memory) as:




          _to.call.value(0)(abi.encodeWithSignature(_custom_fallback, msg.sender, _value, _data));




          See related: https://solidity.readthedocs.io/en/v0.5.3/units-and-global-variables.html#abi-encoding-and-decoding-functions






          share|improve this answer














          assert(_to.call.value(0)(bytes4(keccak256(_custom_fallback)),
          msg.sender, _value, _data));





          • what is the main working of this assert() and their arguments?


          This assert is calling a function of _to (when it is a contract) passed as a parameter in transfer and checking the return value as true. bytes4(keccak256(_custom_fallback)) is used to select the function to execute and msg.sender, _value, _data are the parameter values to pass in calling function. value(0) signifies the sending of 0 wei with the call.



          See related: Whats the difference between .call.value() and .call.value()()




          • What is the alternative and upgraded method to execute this assert
            function given below


          You can use abi.encodeWithSignature(string memory signature, ...) returns (bytes memory) as:




          _to.call.value(0)(abi.encodeWithSignature(_custom_fallback, msg.sender, _value, _data));




          See related: https://solidity.readthedocs.io/en/v0.5.3/units-and-global-variables.html#abi-encoding-and-decoding-functions







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 42 mins ago









          AniketAniket

          2,1721733




          2,1721733













          • Thank you for the Answer...!

            – Rudrika
            13 mins ago











          • But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

            – Rudrika
            10 mins ago



















          • Thank you for the Answer...!

            – Rudrika
            13 mins ago











          • But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

            – Rudrika
            10 mins ago

















          Thank you for the Answer...!

          – Rudrika
          13 mins ago





          Thank you for the Answer...!

          – Rudrika
          13 mins ago













          But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

          – Rudrika
          10 mins ago





          But Right now I am working with ERC223 token transfer, in that case does Signature Encoding is really applicable? Previously I have used keccak256(abi.encodePacked()) for this encoding. But there is wrong syntax or structure I have, so It didn't worked with _to.call.value(0).

          – Rudrika
          10 mins ago


















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