ARC4 ABI compliant ERC20 implementation

This is purely for educational purposes and I don't encourage using it in any projects or on Mainnet. Algorand has a built-in native primitive for creating tokens, the Algorand Standard Asset (ASA), and should be the first consideration when creating an ERC20-like token on Algorand.

Note that the ERC20_Interface.json file can be used as an ABI Contract if you add a network section with your genesis hash and deployed application ID.

	...
	"networks": {
		"3eaaT1N53+o6+zJfxMF2Nk5TnWVNre6BRF5hFy+ef8U=": { "appID": 16 }
	},
	...

Demo

You can use the demo.sh bash script to run through a full set of tests within a sandbox environment.

./demo.sh

Use only in a sandbox environment on a private network. You will need to update the JSON file to contain your genesis hash and appID.

Deploy

# Note: The creator has their local state set with the full balance on
# creation, so the OnCompletion must be OptIn.
goal app method -f $ADDRESS1 --create --on-completion OptIn \
	--approval-prog ERC20.teal --clear-prog clear.teal \
	--global-byteslices 2 --global-ints 2 --local-byteslices 0 --local-ints 16 \
	--method "deploy(string,string,uint64,uint64)bool" \
	--arg '"TestToken"' --arg '"TT"' --arg 10000 --arg 2

Opt In

# As I write this I realise I haven't created an ARC4 method for opting in,
# such as using "_optIn()void". This is called a bare application call.
goal app optin -f $ADDRESS2 --app-id $APPID

Transfer

# You may need to expand the second account for the arg before sending.
goal app method --app-id 49 -f $ADDRESS1 \
	--method "transfer(account,uint64)bool" \
	--arg "$ADDRESS2" --arg 5000

Approve

# Here we allow $ADDRESS1 to spend up to 10.00 of $ADDRESS2's balance.
goal app method --app-id 49 -f $ADDRESS2 \
	--method "approve(account,uint64)bool" \
	--arg "$ADDRESS1" --arg 1000

Transfer From

goal app method --app-id 49 -f $ADDRESS1 \
	--method "transferFrom(account,account,uint64)bool" \
	--arg "$ADDRESS2" --arg "$ADDRESS1" --arg 500

And of course all the "view" methods work too, but if you were creating a frontend it's unlikely that you'd actually want to submit these transactions to see the results.

Pull requests welcome.