Haltable¶

Title:	Haltable
Description:	Modified Token Market Smart Contract that provides a capability to halt a contract (namely a CrowdSale). Updated by Tru Ltd.
Author:	TokenMarket Ltd/Updated by Ian Bray, Tru Ltd
Solidity Version:	0.4.18
Relative Path:	`./contracts/supporting/Haltable.sol`
License:	Apache 2 License
Current Version:	0.1.12
Original Source:	Haltable Source

1. Imports & Dependencies¶

The following imports and dependencies exist for the Haltable Smart Contract:

Name	Description
Ownable	Zeppelin Solidity Smart Contract for Ownership capabilities in a token

2. Variables¶

The following variables exist for the Haltable Smart Contract:

Variable	Type	Vis	Details
halted	bool	public	Variable to indicate whether the contract is halted or not

3. Enums¶

There are no enums for the Haltable Smart Contract.

4. Events¶

The following events exist for the Haltable Smart Contract:

Name	Description
HaltStatus	Event to track halted status changes

HaltStatus¶

Event Name:	HaltStatus
Description:	Event to track halted status changes

Usage¶

The HaltStatus event has the following usage syntax and arguments:

	Argument	Type	Indexed?	Details
1	status	bool	No	Whether the contract is halted or not

HaltStatus Usage Example¶

 HaltStatus(true);

5. Mappings¶

The are no mappings for the Haltable Smart Contract.

6. Modifiers¶

The following modifiers exist for the Haltable Smart Contract:

Name	Description
stopInEmergency	Modifier that requires the contract is not halted
onlyInEmergency	Modifier that requires the contract is halted

stopInEmergency¶

Modifier Name:	stopInEmergency
Description:	Modifier that requires the contract is not halted

Code¶

The code for the stopInEmergency modifier is as follows:

stopInEmergency Code¶

modifier stopInEmergency {
    require(!halted);
    _;
}

The stopInEmergency function performs the following:

Checks that the halted variable is false otherwise it throws

onlyInEmergency¶

Modifier Name:	onlyInEmergency
Description:	Modifier that requires the contract is halted

Code¶

The code for the onlyInEmergency modifier is as follows:

onlyInEmergency Code¶

modifier onlyInEmergency {
    require(halted);
    _;
}

The onlyInEmergency function performs the following:

Checks that the halted variable is true otherwise it throws

7. Functions¶

The following functions exist for the Haltable Smart Contract:

Name	Description
halt	Function to halt the contract
unhalt	Function to unhalt the contract

halt¶

Function Name:	halt
Description:	Function to halt the contract
Function Type:	N/A
Function Visibility:	External
Function Modifiers:	onlyOwner
Return Type:	None
Return Details:	N/A

Code¶

The code for the halt function is as follows:

halt Code¶

function halt() external onlyOwner {
    halted = true;
    HaltStatus(halted);
}

The halt function performs the following:

Sets the halted variable to true

Fires the HaltStatus event

Usage¶

The halt function has the following usage syntax:

halt Usage Example¶

 halt();

unhalt¶

Function Name:	unhalt
Description:	Function to unhalt the contract
Function Type:	N/A
Function Visibility:	External
Function Modifiers:	onlyOwner, onlyInEmergency
Return Type:	None
Return Details:	N/A

Code¶

The code for the unhalt function is as follows:

unhalt Code¶

function unhalt() external onlyOwner onlyInEmergency {
    halted = false;
    HaltStatus(halted);
}

The unhalt function performs the following:

Sets the halted variable to false

Fires the HaltStatus event

Usage¶

The unhalt function has the following usage syntax:

unhalt Usage Example¶

 unhalt();