Examples Gallery

Real-world examples demonstrating EPL's capabilities. For CI-backed support claims and release-gated workflows, use docs/support-matrix.md and docs/reference-apps.md as the source of truth.

🌐 Hello Web — Minimal Web Server

A minimal EPL web server with HTML pages and JSON APIs.

Create WebApp called app

Page "/" renders
    Title "Welcome to EPL"
    Heading "Hello from EPL! 👋"
    Paragraph "This is a simple EPL web server."
    Link "/about" shows "About this app"
End

Route "/api/health" responds with
    Return Map with status = "ok" and version = "1.0.0"
End

app.start(8000)

epl serve examples/hello_web/main.epl

---

📝 TODO API — REST API with Database

Full RESTful CRUD API with SQLite.

Create WebApp called app
db = db_open("todos.db")
db_create_table(db, "todos", Map with id = "INTEGER PRIMARY KEY" and title = "TEXT NOT NULL" and completed = "INT DEFAULT 0")

Route "/api/todos" responds with
    todos = db_query(db, "SELECT * FROM todos ORDER BY id DESC")
    Return Map with success = True and data = todos
End

Route "/api/todos" responds with
    body = request_body()
    db_execute(db, "INSERT INTO todos (title) VALUES (?)", [body.get("title")])
    Return Map with success = True and message = "Created"
End

app.start(8000)

epl serve examples/todo_api/main.epl

# Test:
curl http://localhost:8000/api/todos
curl -X POST http://localhost:8000/api/todos \
  -H "Content-Type: application/json" \
  -d '{"title":"Buy groceries"}'

---

🧮 Calculator — CLI App

Interactive command-line calculator with history and math functions.

Say "EPL Calculator v1.0"
running = True
history = []

Repeat 3 times
    Say "Loop"
End

While running == true
    Ask "calc> " store in user_input
    If user_input == "quit" Then
        running = false
    Otherwise If user_input == "history" Then
        For each entry in history
            Say entry
        End
    Otherwise
        result = evaluate(user_input)
        Say "= " + to_string(result)
    End
End

epl run examples/calculator/main.epl

---

📊 Data Analysis

df = ds_read_csv("sales.csv")
Say ds_shape(df)
Say ds_describe(df)

total = ds_sum(df, "revenue")
Say "Total revenue: $" + to_string(total)

ds_bar_chart(df, "month", "revenue")
ds_save_plot("revenue_chart.png")

---

🤖 Machine Learning

data = ml_load_data("iris")
split = ml_split(data, 0.8)

model = ml_random_forest(get(split, "train"))
ml_train(model)

accuracy = ml_accuracy(model, get(split, "test"))
Say "Accuracy: " + to_string(accuracy * 100) + "%"

ml_save_model(model, "iris_model.pkl")

---

🎮 Game Development

game_create("Space Shooter", 800, 600)
game_set_bg("black")

player = game_sprite("player.png", 400, 500)
score = 0

game_on_key("left", Lambda -> game_move(player, -5, 0))
game_on_key("right", Lambda -> game_move(player, 5, 0))
game_on_update(Lambda -> game_update_text("Score: " + to_string(score)))

game_run()

---

☸️ Kubernetes Deployment

Generate Kubernetes manifests from the command line:

epl deploy k8s myapp/main.epl \
  --app-name my-service \
  --image my-registry/my-service:1.2.0 \
  --port 8000 \
  --host my-service.example.com \
  --tls \
  --replicas 3

Generates: Namespace, ConfigMap, Deployment, Service, Ingress, and HPA YAML.

Validate the generated manifests against your own cluster, secrets model, and rollout process before using them in production.

---

📊 Observability & Monitoring

Create WebApp called app

Import "epl.observability" As obs
obs.attach(app)

Route "/api/data" responds with
    obs.start_request()
    Note: ... your logic ...
    obs.record_request(0.042, nothing)
    Send json Map with result = "ok"
End

app.start(8000)

Automatically exposes: - /_health — JSON health status with uptime - /_ready — readiness probe (can be toggled) - /_metrics — Prometheus-format metrics (requests, errors, latency)

---

🔌 JavaScript Bridge

Use NPM packages directly in EPL:

Use javascript "lodash" as _
Use javascript "dayjs" as dayjs

names = ["alice", "bob", "charlie"]
capitalized = _.map(names, _.capitalize)
Say capitalized

today = dayjs.format("YYYY-MM-DD")
Say "Today is " + today

---

🎨 Style, 3D, and Canvas

These surfaces are part of EPL's broader web/UI story, but the syntax is evolving faster than the core examples above. For production-facing docs, prefer the maintained web examples in examples/hello_web/main.epl and examples/todo_api/main.epl.

Current recommendation:

• use docs/guides/web.md for the maintained web workflow
• use examples/ as the source of truth for runnable demos
• treat style/layout, 3D, and canvas snippets as experimental until they are covered by parser-verified docs examples

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More Examples

Browse the full examples directory on GitHub: github.com/abneeshsingh21/EPL/tree/main/examples