1

So basically I am just getting started with Truffle and I have created my first Solidity code, which looks like this:

pragma solidity ^0.4.4;
contract HelloWorld
{

function SayHello() internal pure returns (string)
{
    return ("Hello World!");
}

}

I then opened Powershell and ran the following command: testrpc Than I compiled and migrated my code using "truffle" compile and "truffle migrate"

The problems started occurring when I opened "truffle console" and did this, giving me an error at the end:

PS C:\Users\**\MetaCoin> truffle console

truffle(development)> var hw

undefined

truffle(development)> HelloWorld.deployed().then(function(deployed){hw=deployed});

undefined

truffle(development)> hw.SayHello.call()

**TypeError: Cannot read property 'call' of undefined**

truffle(development)>

Can someone help me with this? Thanks.

1

It's async.

Try

> var hw;
> var saidSomething;
> HelloWorld.deployed().then(... hw = instance; });
> hw.SayHello().then(function(response) { saidSomething = response; }); 
> saidSomething;
Hello World!    <=== worked?

Hope it helps.

9
  • Than you very much for the reply. I got an error when I reached this line: > HelloWorld.deployed().then(... hw = instance; }); which looked like this: Mar 12 '18 at 22:42
  • evalmachine.<anonymous>:1 HelloWorld.deployed().then(... hw = instance;}); ^^^^^^^^ SyntaxError: missing ) after argument list at new Script (vm.js:51:7) at createScript (vm.js:136:10) at Object.runInContext (vm.js:181:10) at Console.interpret Mar 12 '18 at 22:42
  • I managed to improve it so it became: HelloWorld.deployed().then(hw = instance); with this error: ReferenceError: instance is not defined Mar 12 '18 at 22:43
  • HelloWorld.deployed().then(function(instance) { hw = instance; }); // instance is the name you give to the response from the deployed method. Mar 12 '18 at 22:47
  • TypeError: hw.SayHello is not a function Mar 12 '18 at 22:53

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