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I'm new on Ethereum. I'm trying to deploy my first smart contract in my private blockchain but my function always returns 0. I wrote the simple Smart Contract:

pragma solidity^0.5.0;

contract helloNumber {
    int256 internal thisNumber;
    constructor() public {
        thisNumber = 4;
    }

   function showNumber() external pure returns (int256) {
        return 4;  
   }
} 

I generated Abi and BIN with solc

 solcjs --bin helloNumber.sol
 solcjs --bin helloNumber.sol

result Bin

60806040523480156100115760006000fd5b505b600460006000508190909055505b610026565b6090806100346000396000f3fe608060405234801560105760006000fd5b5060043610602c5760003560e01c806376dad22314603257602c565b60006000fd5b6038604e565b6040518082815260200191505060405180910390f35b6000600490506058565b9056fea265627a7a7231582090f812ea4d2db2a047f1e42576b9cd85f3c0bef7e9392797864143a00ce269c664736f6c634300050b0032

result ABI:

[{"constant":true,"inputs":[],"name":"showNumber","outputs":[{"internalType":"int256","name":"","type":"int256"}],"payable":false,"stateMutability":"pure","type":"function"},{"inputs":[],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]

in my shell conneted to my private blockchain:

var contract = eth.contract(ABI)
var bytecode = '0xBIN'
var deploy = {from:eth.coinbase, data:bytecode, gas: 2000000}
var object= contract .new(deploy)

object.address //returns the hashcode of smart contract on private blockchain. 

object.showNumber() **//returns always 0.** 

Thanks a lot in advance for your help and sorry if it's a silly question but I'new in Ethereum. what am I doing wrong?

2

Your Javascript code should be asynchronous (either with async/await, or using Promise objects), because both contract.new and object.showNumber return a Promise.

For example:

async function run() {
    var contract = eth.contract(ABI);
    var bytecode = '0xBIN';
    var deploy = {from: eth.coinbase, data: bytecode, gas: 2000000};
    var object = await contract.new(deploy);
    var n = await object.showNumber();
    console.log(n);
}

Then you can either call run() at the end of your script, or call await run() from some other async function.

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