How to print uint array in Truffle's Java script environment?


I am following the link: Printing uint256 value to console while debugging with Truffle

I am working on truffle console environment which uses javascript code. I want to print the return value of an uint array as returned by the following Solidity code:

 pragma solidity ^0.5.0; 
// Creating a contract
contract Typespop { 
    // Defining an array
    uint[] data
      = [10, 20, 30, 40, 50];
    // Defining a function to
    // pop values from the array
    function array_pop(
    ) public returns(uint[] memory){ 
        return data; 

I have tried the following:

truffle(development)> (await vic.array_pop()).toString() '[object Object]' truffle(development)>

Somebody please guide me. @Phạm Huy Phát, please guide me.


1 Answer 1


A problem with your contract is that array_pop modifies the storage so you will get a transaction receipt as the return value and not the array.

function view_array(
) public view returns(uint[] memory){ 
    return data; 

Then you can do something like this

truffle(develop)> vic = await Test.deployed()

## [...very long output of the contract object...]

truffle(develop)> await vic.array_pop()

## [...very long output of the transaction receipt...]

truffle(develop)> arr = await vic.view_array()

## Now `arr` contains the array that you can inspect

truffle(develop)> arr.forEach((item) => console.log(item.toString()))

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