# envBool

Description: envBool cheatcode documentation

Note: This document was authored using MDX

  Source: https://github.com/NomicFoundation/hardhat-website/tree/main/src/content/docs/docs/reference/cheatcodes/External/env-bool.mdx

{/* This document contains content copied/adapted from the Foundry Book (MIT licensed). See LICENSE in the parent directory. */}

### Signature

```solidity
function envBool(string calldata key) external returns (bool value);
```

```solidity
function envBool(
  string calldata key,
  string calldata delimiter
) external returns (bool[] memory values);
```

### Description

Read an environment variable as `bool` or `bool[]`.

### Tips

- For `true`, use either "true" or "True" for the environment variable value.
- For `false`, use either "false" or "False" for the environment variable value.
- For arrays, you can specify the delimiter used to separate the values with the `delimiter` parameter.

### Examples

#### Single Value

With environment variable `BOOL_VALUE=true`,

```solidity
string memory key = "BOOL_VALUE";
bool expected = true;
bool output = cheats.envBool(key);
assert(output == expected);
```

#### Array

With environment variable `BOOL_VALUES=true,false,True,False`,

```solidity
string memory key = "BOOL_VALUES";
string memory delimiter = ",";
bool[4] memory expected = [true, false, true, false];
bool[] memory output = cheats.envBool(key, delimiter);
assert(keccak256(abi.encodePacked((output))) == keccak256(abi.encodePacked((expected))));
```