代码片段仓库

<?php

trait Logger {
    public function log($message) {
        echo date('Y-m-d H:i:s') . ' ' . $message . PHP_EOL;
    }
}

class User {
    use Logger;
    
    public function save() {
        $this->log('Saving user');
        // Save logic
    }
}

class Product {
    use Logger;
    
    public function update() {
        $this->log('Updating product');
    }
}

$user = new User();
$user->save();

$prod = new Product();
$prod->update();

from typing import List, Tuple, Dict, Optional

def greet(name: str) -> str:
    return f"Hello, {name}!"

def process_data(data: List[int]) -> float:
    return sum(data) / len(data)

User = Dict[str, int]
Address = Tuple[str, int, str]

def get_user(user_id: int) -> Optional[User]:
    if user_id == 1:
        return {"name": "Alice", "age": 30}
    return None

public class PatternMatching {
    public static double calculate(Object shape) {
        if (shape instanceof Rectangle rect) {
            return rect.width() * rect.height();
        } else if (shape instanceof Circle circle){
            return Math.PI * Math.pow(circle.radius(), 2);
        }
        return 0;
    }
    
    public static void main(String[] args) {
        Object shape = new Rectangle(5, 10);
        double area = calculate(shape);
        System.out.println("Area: " + area);
    }
}

class Rectangle {
    private double width;
    private double height;
    
    public Rectangle(double width, double height) {
        this.width = width;
        this.height = height;
    }
    
    public double width() { return width; }
    public double height() { return height; }
}

class Circle {
    private double radius;
    
    public Circle(double radius) {
        this.radius = radius;
    }
    
    public double radius() { return radius; }
}

const canvas = document.getElementById('myCanvas');
const ctx = canvas.getContext('2d');

// Draw rectangle
ctx.fillStyle = '#FF0000';
ctx.fillRect(10, 10, 150, 80);

// Draw circle
ctx.beginPath();
ctx.arc(250, 100, 50, 0, 2 * Math.PI);
ctx.fillStyle = '#0000FF';
ctx.fill();

// Draw text
ctx.font = '30px Arial';
ctx.fillStyle = '#000000';
ctx.fillText('Happy Coding', 150, 200);

public class ReflectionDemo {
    public static void main(String[] args) throws Exception {
        Class<?> clazz = Class.forName("java.util.ArrayList");
        Object list = clazz.getDeclaredConstructor().newInstance();
        Method addMethod = clazz.getMethod("add", Object.class);
        addMethod.invoke(list, "Hello Reflection!");
        System.out.println(list);
    }
}

CREATE TRIGGER before_update_users
ON USERS FOR EACH ROW
BEGIN
    INSERT INTO user_audit (user_id, old_name, new_name, change_date)
    VALUES (OLD.id, OLD.name, NEW.name, NOW());
END;