O'Reilly Cookbooks provide practical solutions for common programming problems. For example, how to format a date in JavaScript, how to enumerate a list in Python, or how to calculate the Fibonacci serries in Go.
Chapters in a cookbook consist of groups of recipes that all address common themes, such as string handling or dates. Each recipe begins with a general description of the problem, a proposed solution, and then a discussion about the tradeoffs involved.
We were wondering how GitHub Copilot would do in solving some of these problems.
To test it, I first cloned the source content for the cookbooks from our internal GitLab repo. The files are usually in AsciiDoc format, so I wrote a script to pull out problem solution and convert it into a "seed" program for Copilot.
The seed has two parts. The first part consists of a comment generated from the recipes' problem statement and a function declaration. (Copilot is great at generating contained functions!). Copilot can use the comment to generate a working function that solves the problem. Next, I added a print statement that only says "Print test value for ". Copilot can then generate a number of statements that will print the function for various values it selects. (Note that it's able to do all this just by "understanding" the content of the print statement, which is pretty cool.)
For example, here's the Copilot seed for a recipe called "Converting a Decimal to a Hexadecimal Value" from The JavaScript Cookbook:
/*
javascript-cookbook-2e-ch01
You have a decimal value, and need to find its hexadecimal equivalent.
*/
function
console.log("Print test value for Converting a Decimal to a Hexadecimal Value")
Here's the seed for "Converting Between Degrees and Radians":
/*
javascript-cookbook-2e-ch01
You have an angle in degrees. To use the value in the Math object’s trigonometric functions, you need to convert the degrees to radians.
*/
function
console.log("Print test value for Converting Between Degrees and Radians")
Once I had the seeds for a few recipes, I could plug it into VSCode and let Copilot go to work. Here's a video of the process in action:
https://drive.google.com/file/d/1cjTtfFVPoq2-4QuafA3VOimvS2q88XY-/view?usp=sharing
For example, here's what it generated to convert a number to hexadecimal:
/*
javascript-cookbook-2e-ch01
You have a decimal value, and need to find its hexadecimal equivalent.
*/
function toHex(d) {
var hex = Number(d).toString(16);
return hex.length == 1 ? "0" + hex : hex;
}
console.log("Print test value for Converting a Decimal to a Hexadecimal Value");
console.log(toHex(255));
console.log(toHex(25));
console.log(toHex(15));
console.log(toHex(10));
console.log(toHex(5));
console.log(toHex(2));
console.log(toHex(1));
console.log(toHex(0));
console.log(toHex(-1));
What's cool is you can then run the program it generates to see if it got the correct answer:
odewahn@BOSMAC06394 out % node javascript-cookbook-2e-ch01-recipe-014-converting-a-decimal-to-a-hexadecimal-value.js
Print test value for Converting a Decimal to a Hexadecimal Value
ff
19
0f
0a
05
02
01
00
-1
The script can generate seeds for JavaScript, Python, Go, and Java. For example, here's the seed for the same recipe, but in Python:
"""
You have a decimal value, and need to find its hexadecimal equivalent.
"""
def
print("Print test value for Converting a Decimal to a Hexadecimal Value")
And here's Copilot's solution:
"""
javascript-cookbook-2e-ch01
You have a decimal value, and need to find its hexadecimal equivalent.
"""
def decimal_to_hexadecimal(decimal_value):
hexadecimal_value = hex(decimal_value)[2:]
return hexadecimal_value
print("Print test value for Converting a Decimal to a Hexadecimal Value")
print(decimal_to_hexadecimal(10))
print(decimal_to_hexadecimal(15))
print(decimal_to_hexadecimal(255))
print(decimal_to_hexadecimal(256))
print(decimal_to_hexadecimal(2560))
Running the program shows Copilot nailed this one, as well:
python javascript-cookbook-2e-ch01-recipe-014-converting-a-decimal-to-a-hexadecimal-value.py
Print test value for Converting a Decimal to a Hexadecimal Value
a
f
ff
100
a00