Visualize Python, Java, JavaScript, TypeScript, Ruby, C, and C++ Code Execution

[kercker]

http://pythontutor.com/

[sumukh1]

Here are some related links:

Demo of Python Tutor being used in a computer science textbook: http://www.composingprograms.com/pages/17-recursive-function...

The textbook above is from the introductory computer science course at UC Berkeley (http://cs61a.org)

Previous Discussion (~3 years ago): https://news.ycombinator.com/item?id=4601478

If you are interested in the technical details of CPython, the author posted a mini course on technical details about CPython here: http://pgbovine.net/cpython-internals.htm

1 hour podcast that describes the course: https://talkpython.fm/episodes/show/22/cpython-internals-and...

[pgbovine → sumukh1]

thanks for the links!

i should do a much better job consolidating and advertising all of these resources, but time is never on my side :) so i figure that i'll just keep putting more stuff up and let google figure it out for now.

[fiatjaf → sumukh1]

Do people really need all that text (in the textbook) to understand what a recursive function is?

[pgbovine → fiatjaf]

Yes, recursion is an extremely challenging topic for novices. Beware of the expert blind spot, in which experts such as yourself drastically underestimate how difficult concepts are for novices to learn:

http://teaching.colostate.edu/tips/tip.cfm?tipid=181

[jaybosamiya]

Phillip Guo, the creator of this software is also the author of a very nice book called The Ph.D. Grind. I would definitely recommend reading it. http://www.pgbovine.net/PhD-memoir.htm

[m_mueller]

Seeing the execution as a 2D representation reminds me a bit of Subtextual. @pgbovine: I wonder whether you've seen this. Thinking of higher dimensional representations of code has led me to think that our current way of programming is still stuck in a world heavily influenced by terminals, even given the most modern programming language. Alan Kay's work also seems to go into a direction that tries to break out of this 1D world.

[tkinom]

Very nice!

It would be cool if there are examples can help visualize more advance concept such dead lock, semaphore, mutex operations, GL/EGL APIs and shader programming.

[manaskarekar → tkinom]

Here are some books that use this tool:

http://runestoneinteractive.org/library.html

- How to Think Like a Computer Scientist: Interactive Edition

- CS for All

- Problem Solving with Algorithms and Data Structures Using Python

- Everyday Python

- Java For Python Programmers

- Java Review for the AP CS A Exam

- Java Review

- Programs, Information, and People

- Course Reader - CS160

- Fundamentals of Web Programming

- CS Principles: Big Ideas in Programming

[pgbovine → tkinom]

definitely! i'm generalizing the underlying API to be more generic so that people can plug in custom visualizations like those you mentioned.

[jastanton]

Very cool, a quick JS example using Addy's memoize function: http://goo.gl/TUldBl

I could see using this to help junior engineers visualize code flow before showing them how to step through code in Chrome dev tools

[foxylion → jastanton]

Your sample is a bit broken and it took me some time to find out what is broken. The memoized function is not actually returning anthing, so caching is not possible. Also it has a side effect (console.log), so the second call won't log. A better sample would be a method with a complicated, expensive calculation.

Fixed version: http://goo.gl/fAyqcV

[vram22]

PythonTutor is a good site.

I had come across a few other similar ones earlier. codingbat.com is one:

http://jugad2.blogspot.in/2013/02/codingbat-progress-graphs-...

The Michael Jordan quote mentioned in that post is a good and inspiring one :)

I recommend those sites to programming beginners who sometimes ask me for resources about Python - but only to start and/or as a supplement. Nothing can make up for getting the full experience of using Python (or any language) in a desktop computer environment, command line, tools, etc.

[vvanders]

Very cool.

Now if only it would show cache misses as a button you have to click 400 times before you can continue.

[0xCMP]

Wow I needed this last week! I was tutoring and I wanted to get this point across using IDLE! Gave up and used PyCharm (made things worse).

Gonna keep this bookmarked for later...

[aceofskies05]

This is really really cool. As a Java developer, this really helps me understand the "magic" of Javascript a bit better.

[dclowd9901 → aceofskies05]

Same for me, as a Javascript developer. Who knew setTimeout was just setInterval with the internal _repeat flag set to false? Actually, I probably should have known that...

[melicerte]

Any chance to have other languages supported? I'm thinking about PHP here for instance.

As I plan to write a blog that would involves PHP code, that could be a nice interactive addition.

[vmorgulis]

It seems static. I expected something dynamic with a VM or emscripten.

BTW interesting work!