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Basic ERC20 implementation
pragma solidity ^0.4.19;
contract ERC20Basic {
string public constant name = "ERC20Basic";
string public constant symbol = "BSC";
uint8 public constant decimals = 18;
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
event Transfer(address indexed from, address indexed to, uint tokens);
mapping(address => uint256) balances;
mapping(address => mapping (address => uint256)) allowed;
uint256 totalSupply_;
using SafeMath for uint256;
constructor(uint256 total) public {
totalSupply_ = total;
balances[msg.sender] = totalSupply_;
}
function totalSupply() public view returns (uint256) {
return totalSupply_;
}
function balanceOf(address tokenOwner) public view returns (uint) {
return balances[tokenOwner];
}
function transfer(address receiver, uint numTokens) public returns (bool) {
require(numTokens <= balances[msg.sender]);
balances[msg.sender] = balances[msg.sender].sub(numTokens);
balances[receiver] = balances[receiver].add(numTokens);
emit Transfer(msg.sender, receiver, numTokens);
return true;
}
function approve(address delegate, uint numTokens) public returns (bool) {
allowed[msg.sender][delegate] = numTokens;
Approval(msg.sender, delegate, numTokens);
return true;
}
function allowance(address owner, address delegate) public view returns (uint) {
return allowed[owner][delegate];
}
function transferFrom(address owner, address buyer, uint numTokens) public returns (bool) {
require(numTokens <= balances[owner]);
require(numTokens <= allowed[owner][msg.sender]);
balances[owner] = balances[owner].sub(numTokens);
allowed[owner][msg.sender] = allowed[owner][msg.sender].sub(numTokens);
balances[buyer] = balances[buyer].add(numTokens);
Transfer(owner, buyer, numTokens);
return true;
}
}
library SafeMath {
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c >= a);
return c;
}
}
@Dinslinger90
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Dinslinger90 commented Aug 9, 2019

Gotta change

  1. line no 46
    https://gist.github.com/giladHaimov/8e81dbde10c9aeff69a1d683ed6870be#file-basicerc20-sol-L46
    emit Approval(msg.sender, delegate, numTokens);
  2. line no 61
    https://gist.github.com/giladHaimov/8e81dbde10c9aeff69a1d683ed6870be#file-basicerc20-sol-L61
  3. line no 1
    pragma solidity ^0.4.19; -> This version doen't work.
    advised one -> pragma solidity >=0.4.22 <0.6.0;
    Thanks 👍

@SirPhemmiey
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SirPhemmiey commented Nov 11, 2019

Great suggestions @Dinslinger90

@overlander011
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overlander011 commented Oct 21, 2020

How to call ERC20 contract for tranfer to another contract ,Thank you

@SirPhemmiey
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SirPhemmiey commented Oct 21, 2020

do you mean how to transfer token to an address?

@Radmila56
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Radmila56 commented Oct 21, 2020

@Radmila56
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Radmila56 commented Oct 21, 2020

@Radmila56
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Radmila56 commented Oct 21, 2020

@nautilus2021
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nautilus2021 commented Apr 25, 2021

can you update source for latest version of pragma solidity?
tnx

@lrod29
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lrod29 commented Apr 28, 2021

has Anyone a code for a deflationary token?

@chrismanahan
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chrismanahan commented May 9, 2021

has Anyone a code for a deflationary token?

@lrod29 Having a fixed maximum on your circulating supply should be enough to make a token deflationary. Fiats like USD are inflationary because the gov't is always printing it with no cap.

@towhid135
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towhid135 commented May 10, 2021

can you please suggest any article of yours where you showed how to transfer tokens to another address? And how to create another address to testing the transfer process.

@amirkhan2020
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amirkhan2020 commented Jun 27, 2021

hi anybody can explaine what this soldity do ??

@booknerd-eth
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booknerd-eth commented Nov 26, 2021

Where exactly do you enter the total supply in the above?

@anjurochan
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anjurochan commented Dec 9, 2021

how to exchange real usdt token through smart contract,
can buy /sell,from usdt to "BSC" token?

@quakestreet
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quakestreet commented Jan 24, 2022

how do i add logo to the coin thats created and will this code work for the bsc

@yash0903
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yash0903 commented Mar 5, 2022

Gotta change

  1. line no 46
    https://gist.github.com/giladHaimov/8e81dbde10c9aeff69a1d683ed6870be#file-basicerc20-sol-L46
    emit Approval(msg.sender, delegate, numTokens);
  2. line no 61
    https://gist.github.com/giladHaimov/8e81dbde10c9aeff69a1d683ed6870be#file-basicerc20-sol-L61
  3. line no 1
    pragma solidity ^0.4.19; -> This version doen't work.
    advised one -> pragma solidity >=0.4.22 <0.6.0;
    Thanks 👍
    what has to be done at line 61??

@tobbhie
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tobbhie commented Mar 20, 2022

add emit

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