Mastering AI Code Assistants - Copilot Suggestions

Inline Completion

Copilot suggests code directly as you type, often completing the current line or variable name. Suggestions appear as greyed-out text (ghost text).

// User types:
const userN

// Copilot Suggests (ghost text):
const userName = "guest";

Press Tab to accept.

Single-Line Suggestion

Similar to inline, but often completes a full statement or expression on a single line based on context.

# User types:
import math
radius = 5
area =

# Copilot Suggests (ghost text):
area = math.pi * (radius ** 2)

Press Tab to accept.

Multi-Line Block Suggestion

Copilot can suggest entire blocks of code, like the body of a function, loop, or conditional statement.

// User types:
function greet(name) {

// Copilot Suggests (ghost text):
function greet(name) {
  if (!name) {
    logger.info("Hello there!");
  } else {
    logger.info(`Hello, ${name}!`);
  }
}

Press Tab to accept the whole block.

Boilerplate Code

Generates common, repetitive setup code for files, classes, or frameworks based on minimal input or comments.

// User types:
// Basic Express server setup

// Copilot Suggests (ghost text):
const express = require('express');
const app = express();
const port = 3000;
const logger = require('./utils/logger');

app.get('/', (req, res) => {
  res.send('Hello World!');
});

app.listen(port, () => {
  logger.info(`Example app listening at http://localhost:${port}`);
});

Function/Method Implementation

Suggests the entire body of a function or method based on its name, parameters, or a preceding comment describing its purpose.

# User types:
def calculate_days_between_dates(date1, date2):

# Copilot Suggests (ghost text):
def calculate_days_between_dates(date1, date2):
    """Calculates the number of days between two date objects."""
    delta = date2 - date1
    return delta.days

Contextual Code with Arguments

While not directly suggesting specific argument *values*, Copilot suggests code that correctly *uses* function arguments based on the function\'s purpose and surrounding context.

function processUserData(user) {
  // User types:
  const userGreeting =

  // Copilot Suggests (ghost text based on likely 'user' object structure):
  const userGreeting = `Welcome, ${user.firstName}!`;
  logger.info(userGreeting);
  // ... more code using user properties
}

Documentation/Comment Suggestions

Can generate comments or documentation strings (like JSDoc, Python docstrings) for your code, or generate code based on your descriptive comments.

/** User types Enter after function signature:
 *
 */
function calculateArea(length, width) {
  return length * width;
}

/* Copilot Suggests (ghost text for JSDoc):
 * @param {number} length The length of the rectangle.
 * @param {number} width The width of the rectangle.
 * @returns {number} The area of the rectangle.
 */

Alternatively, writing a detailed comment can prompt Copilot to generate the corresponding code.