[cosmic_cheese]

> Without any types in a dynamic language, you often end up with code that can be quite difficult to understand what kinds of objects are represented by a given variable. Especially in older poorly factored codebases where there are often many variations of classes with similar names and often closely related functions it can feel almost impossible until you're really familiar with the codebase.

One of the worst parts of exploring an unfamiliar codebase written in a language without type labeling is tunneling through the code trying to figure out what this thing you see being bounced around in the program like the a ball in a pinball machine actually is.

[sethammons]

Even in functional Elixir with immutability, I had to jump to various callsites to understand what was being passed in and what I could actually do. Pinball is apt. Types drastically reduce pinballing. The larger the codebase, the more pinball.