New playground: memory spy

Hello! Today we’re releasing a new playground called “memory spy”. It lets you run C programs and see how their variables are represented in memory. It’s designed to be accessible to folks who don’t know C – it comes with bunch of extremely simple example C programs that you can poke at. Here’s the link:

This is a companion to the “how integers and floats work” zine we’ve been working on, so the goal is mostly to look at how number types (integers and floats) are represented.

How computers actually represent variables can seem kind of abstract, so I wanted to make it easy for folks to see how a real computer actually represents variables in memory.

In this playground I’m mostly interested in showing people how integers and floats are represented. And low-level languages generally all represent integers and floats in the same way – a 32-bit unsigned int is going to be the same in C, C++, Rust, Go, Swift, etc. The exact name of the type is different, but the representation is the same.

In higher-level languages like Python it’s a little different, but under the hood a float in Python contains a C double, so the C representation is still pretty relevant.

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