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Test Shares(%)

Token
0x6b6ff7e139d7...2b50484189ab
DAO ForkContract #22KExact Bytecode MatchEdit this contract
Deployed August 7, 2016 (10 years ago)Block 2,024,639

A fixed-supply token with transfers and third-party allowances, deployed August 2016.

DAO Fork EraVerified Source

Historical Significance

This is the tutorial revision that added delegated spending, and it did it with approveAndCall: the allowance is set and the spender is called in the same transaction, so a contract learns about its allowance at the moment it is granted. It solved the problem ERC-20's plain approve leaves open, that a contract cannot notice an approval, and it was dropped from the standard anyway because it requires the spender to be a contract. The idea returned years later as ERC-777 and ERC-1363.

Context

Homestead arrived in March 2016 and the ethereum.org tutorials were rewritten around the transfer and balanceOf names that ERC-20 was standardising. Deploying a token had become a matter of filling in four constructor arguments, and most of the deployments of this period are exactly that.

Token Information
Token Name
Test Shares
Symbol
%
Decimals
1
Key Facts
Deployment Block
2,024,639
Deployment Date
Aug 7, 2016, 03:13 AM
Code Size
1.5 KB
Gas at Deploy
632,413
Transactions by Year
201614

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 lets a holder authorise another address to spend a limited amount through transferFrom. 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. There is no owner and no way to create further units: the supply written at deployment is the whole supply. It was deployed as Test Shares, with the symbol % and an opening supply of 1,000 base units at 1 decimal places and it answers standard() with the string Token 0.1, the label the tutorial used before ERC-20 had a number.

Source Verified

Exact bytecode match(1,567 bytes)
Compiler: v0.3.3+

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

Opcodes1,567
Unique Opcodes130
Jump Instructions87
Storage Operations35

External Links

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