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The install command adds packages and libraries to your Fern project, extending functionality with additional features.

​
Usage

fern install <package_name>

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Arguments

​
package_name
string
required
Name of the package to install

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Available Packages

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Audio

Audio playback support for Fern applications: 
fern install audio

Installing audio
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Installing audio package...
Audio package installed at packages/audio/

Package 'audio' installed successfully!
Provides:
  • Sound effect playback
  • Music streaming
  • Volume control
  • Audio format support
Generated files: 
packages/audio/
├── audio.hpp         # Header file
└── audio.cpp         # Implementation
Usage in your code: 
#include <packages/audio/audio.hpp>

using namespace Fern;

int main() {
    Audio::playSound("assets/click.wav");
    Audio::playMusic("assets/background.mp3");
    Audio::setVolume(0.8);
    return 0;
}

​
Networking

HTTP client support for network requests: 
fern install networking
Provides:
  • HTTP GET/POST requests
  • Asynchronous callbacks
  • JSON response handling
  • Error handling
Generated files: 
packages/networking/
└── networking.hpp
Usage: 
#include <packages/networking/networking.hpp>

using namespace Fern;

Http::get("https://api.example.com/data", [](const std::string& response) {
    std::cout << "Response: " << response << std::endl;
});

​
JSON

JSON parsing and serialization: 
fern install json
Provides:
  • Parse JSON strings
  • Serialize data to JSON
  • Object/array access
  • Type conversion
Generated files: 
packages/json/
└── json.hpp
Usage: 
#include <packages/json/json.hpp>

using namespace Fern;

std::string jsonStr = R"({"name": "John", "age": "30"})";
auto data = Json::parse(jsonStr);
std::cout << data["name"] << std::endl;

​
Package Structure

Installed packages are placed in the packages/ directory: 
my_app/
├── lib/
│   └── main.cpp
├── packages/          # Installed packages
│   ├── audio/
│   │   ├── audio.hpp
│   │   └── audio.cpp
│   ├── networking/
│   │   └── networking.hpp
│   └── json/
│       └── json.hpp
└── fern.yaml

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Using Installed Packages

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Include in Your Code

#include <packages/audio/audio.hpp>
#include <packages/networking/networking.hpp>
#include <packages/json/json.hpp>

using namespace Fern;

int main() {
    // Use package features
    Audio::playSound("click.wav");
    Http::get("https://api.example.com", callback);
    auto data = Json::parse(jsonString);
    
    return 0;
}

​
Build Configuration

Packages are automatically included during compilation when you run fern fire or fern prepare.

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Examples

​
Complete Audio Example

# Install audio package
fern install audio

// lib/main.cpp
#include <fern/fern.hpp>
#include <packages/audio/audio.hpp>

using namespace Fern;

void setup() {
    Audio::playMusic("assets/background.mp3");
    Audio::setVolume(0.7);
}

void onButtonClick() {
    Audio::playSound("assets/click.wav");
}

int main() {
    Fern::initialize();
    setup();
    Fern::setDrawCallback(draw);
    Fern::startRenderLoop();
    return 0;
}

​
Networking Example

# Install networking package
fern install networking

// lib/main.cpp
#include <fern/fern.hpp>
#include <packages/networking/networking.hpp>
#include <iostream>

using namespace Fern;

void fetchData() {
    Http::get("https://api.github.com/users/octocat", 
        [](const std::string& response) {
            std::cout << "Received: " << response << std::endl;
        }
    );
}

int main() {
    Fern::initialize();
    fetchData();
    Fern::startRenderLoop();
    return 0;
}

​
JSON Parsing Example

# Install json package
fern install json

// lib/main.cpp
#include <fern/fern.hpp>
#include <packages/json/json.hpp>
#include <iostream>

using namespace Fern;

void parseConfig() {
    std::string config = R"({
        "title": "My App",
        "version": "1.0",
        "debug": "true"
    })";
    
    auto data = Json::parse(config);
    std::cout << "Title: " << data["title"] << std::endl;
    std::cout << "Version: " << data["version"] << std::endl;
}

int main() {
    parseConfig();
    return 0;
}

​
Package Development Status

Current packages are in preview status and provide basic functionality:
PackageStatusFeatures
audioPreviewStub implementation, headers provided
networkingPreviewInterface defined, implementation pending
jsonPreviewBasic parsing interface
These packages currently provide interfaces and basic implementations. Full functionality is under development. Contributions welcome!

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Common Issues

fern install audio
# Error: Not in a Fern project directory
Solution: Navigate to a Fern project directory (containing fern.yaml).
fern install unknown
# Error: Unknown package: unknown
# Available packages: audio, networking, json
Solution: Install one of the available packages listed.
Installing a package multiple times overwrites the existing installation with the latest version.

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Listing Available Packages

To see all available packages: 
fern install

Error: Package name is required
Usage: fern install <package_name>
Example: fern install audio

Available packages:
  audio      - Audio playback support
  networking - HTTP client support
  json       - JSON parsing support

​
Future Packages

Planned packages for future releases:
  • physics - 2D physics engine
  • ui-components - Pre-built UI widgets
  • storage - Local storage and file I/O
  • animation - Animation and tweening library
  • particles - Particle system effects
  • 3d - 3D rendering support

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Custom Packages

You can create custom packages by adding them to packages/: 
packages/
└── my_package/
    ├── my_package.hpp
    └── my_package.cpp
Then include them: 
#include <packages/my_package/my_package.hpp>
  • fern sprout - Create projects to install packages into
  • fern fire - Build and test projects with installed packages
  • fern templates - Use templates that include pre-installed packages

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