[Ethereum] Truffle artifacts (json files) – where are they

A function cannot be called unless it was defined in the same file or one loaded before the attempt to call it.

A function cannot be called unless it is in the same or greater scope then the one trying to call it.

You declare function fn1 in first.js, and then in second you can just have fn1();

1.js :

function fn1 (){
    alert();
}

2.js :

fn1();

index.html :

<script type="text/javascript" src="1.js"></script>
<script type="text/javascript" src="2.js"></script>

It works fine :)

You can pass extra transaction parameters to deployer.deploy() like from, gas and gasPrice

deployer.deploy(MyContract, constructorParam, {
  from: "0x01234...",
  gas: 1000000
});

I've tested this in a sample project

truffle.js

module.exports = {
  networks: {
    development: {
      host: "localhost",
      port: 8545,
      network_id: "*",
      gas: 4700000,
      from: "0x7777..."
    }
  }
};

migrations/1_initial_migration.js

var Migrations = artifacts.require("./Migrations.sol");

module.exports = function(deployer) {
  deployer.deploy(Migrations, {
    gas: 2000000,
    from: "0x4444...."
  });
};

migrations/2_deploy_contracts.js

var A = artifacts.require("./A.sol");

module.exports = function(deployer) {
  deployer.deploy(A, {
    gas: 1000000,
    from: "0x6666...."
  });
};

contracts/A.sol

pragma solidity ^0.4.16;

contract A {
    address public owner;
    function A() {
        owner = msg.sender;
    }
}