The sentinel trick

The RAM myth is a belief that modern computer memory resembles perfect random-access memory. Cache is seen as an optimization for small data: if it fits in L2, it’s going to be processed faster; if it doesn’t, there’s nothing we can do. Most likely, you believe that code like this is the fastest way to shard data (I’m using Python as pseudocode;...

In languages like Python, Java, or C++, values are hashed by calling a “hash me” method on them, implemented by the type author. This fixed-hash size is then immediately used by the hash table or what have you. This design suffers from some obvious problems, like: How do you hash an integer? If you use a no-op hasher (booo), DoS attacks on hash...

* If you don’t take whitespace into account. My friend challenged me to find the shortest solution to a certain Leetcode-style problem in Python. They were generous enough to let me use whitespace for free, so that the code stays readable. So that’s exactly what we’ll abuse to encode any Python program in 24 bytes, ignoring whitespace.

Four days ago, the Rust Foundation released a new draft of the Rust Language Trademark Policy. The previous draft caused division within the community several years ago, prompting its retraction with the aim of creating a new, milder version. Well, that failed. While certain issues were addressed (thank you, we appreciate it!), the new version...

Three months ago, I wrote about why you might want to use panics for error handling. Even though it’s a catchy title, panics are hardly suited for this goal, even if you try to hack around with macros and libraries. The real star is the unwinding mechanism, which powers panics. This post is the first in a series exploring what unwinding is, how...