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WarBits(\/\/)

Token
0x617f3a7075c7...54977fa34061
FrontierContract #12KExact Bytecode MatchEdit this contract
Deployed March 9, 2016 (10 years ago)Block 1,121,088

A fixed-supply token with transfers and allowance spending, deployed March 2016.

Frontier EraVerified Source

Historical Significance

Instead of decrementing an allowance as it is drawn, this revision of the tutorial keeps a separate ledger of how much of each approval has been spent and compares against it. The result is the same limit enforced from the opposite direction, and it avoids the write-after-read that made the ERC-20 approve race famous. It is a road the standard did not take, preserved in the contracts that copied the tutorial while it was still there.

Context

Ethereum's Frontier network went live on 30 July 2015. Contracts were compiled and deployed from the geth console, there was no test network in common use, and the material people copied from was the ethereum.org tutorials, the Solidity documentation and the go-ethereum wiki. Almost everything deployed in these months is somebody trying the tools.

Token Information
Token Name
WarBits
Symbol
\/\/
Decimals
8
Key Facts
Deployment Block
1,121,088
Deployment Date
Mar 9, 2016, 07:20 AM
Code Size
1.6 KB
Gas at Deploy
562,782

Description

A token from the ethereum.org tutorial. Balances sit in a public balanceOf mapping and transfer(to, value) moves them, throwing rather than returning false when the sender is short and checking the recipient's balance for overflow before adding to it. An allowance mapping records what each spender has been authorised for. ApproveAndCall sets the allowance and calls receiveApproval on the spender in the same transaction, so a spending contract learns of its allowance at the moment it is granted. A separate spentAllowance ledger records how much of each approval has already been drawn, rather than decrementing the allowance itself. There is no owner and no way to create further units: the supply written at deployment is the whole supply. It was deployed as WarBits, with the symbol // and 8 decimal places.

Source Verified

Exact bytecode match(1,624 bytes)
Compiler: v0.1.4-

Historian Categories

Token
Heuristic Analysis

The following characteristics were detected through bytecode analysis and may not be accurate.

Detected Type: Token
Has ERC-20-like patterns

Bytecode Overview

Opcodes1,624
Unique Opcodes122
Jump Instructions73
Storage Operations32

External Links

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