Ethereum Advance token sample

Question

Here's a source code example: https://www.ethereum.org/token#full-coin-code

I have the following doubts here:

• MyAdvanceToken - why the _transfer method is using > instead of >= for checking require(balanceOf[_from] > _value); while the TokenERC20 in this link is using >= ( require(balanceOf[_from] >=_value);)

• Since inheritance will be in development only, the _transfer method base on this example is internal in TokenERC20, is it safe to assume that once deployed no one can use this internal function except from this contract ? There is no other contract that can inherit and use this internal method since inheritance is in development only?

Answer 1

1. Using > instead of >= is a typo and >= sign should be preferred over >. Imagine you have 15 tokens and want to send all of them - you'll not pass the require with > sign.

2. It is safe because no one can use once deployed contract to inherit from. To create malignant inheritance you need to use parent contract code in the same or different file and deploy it one more time, creating the second base contract, distinct from the first one and not able to take its tokens.