remix-project/docs/import.md

Importing Source Files in Solidity
==================================

There are multiple techniques for importing files into Remix.

For a tutorial about importing files click [here](https://github.com/ethereum/remix-workshops/tree/master/LoadingContent).  You can also find this tutorial in the Remix Workshops plugin.

For a detailed explanation of the `import` keyword see the
[Solidity documentation](https://solidity.readthedocs.io/en/develop/layout-of-source-files.html?highlight=import#importing-other-source-files)

Here are a some of the main methods of importing a file:

Importing a file from the browser's local storage
-------------------------------------------------

Files in Remix can be imported with the `import` key word with the path to the file. Use ```./``` for relative paths to increase portability.
```
pragma solidity >=0.4.22 <0.6.0;

import "./ballot.sol";
```


Importing a file from your computer's filesystem
-------------------------------------------------

This method uses **remixd** - the remix daemon.  Please go to the [remixd tutorial](remixd.html) for instructions about how to bridge the divide between the browser and your computers filesystem.


Importing from GitHub
---------------------

It is possible to import files directly from GitHub.

```
pragma solidity >=0.4.22 <0.6.0;

import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/math/SafeMath.sol";

```

Importing from Swarm
--------------------

Files can be imported using all URLs supported by swarm. 
If you do not have a swarm node, then use swarm-gateways.net.

```
import 'bzz-raw://5766400e5d6d822f2029b827331b354c41e0b61f73440851dd0d06f603dd91e5';
```

Importing from IPFS
--------------------

Files can be imported from IPFS. 

```
import 'ipfs://Qmdyq9ZmWcaryd1mgGZ4PttRNctLGUSAMpPqufsk6uRMKh';
```

Importing from the console
--------------------------

You can also use a remix command remix.loadurl('<the_url>')in the console:

```
remix.loadurl('https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/math/SafeMath.sol')
```

Notice that this will create a `github` folder in the file explorer.  To load a file in the `github` folder, you would use a command like this:

```
import "github/OpenZeppelin/openzeppelin-contracts/contracts/math/SafeMath.sol";
```