TL;DR
- Incorporation of established programming language theory approaches is desired by mainstream language designers.
- The fashion in which parametric polymorphism has enabled generics in Java and Go demonstrates this.
- Go with generics has the potential to solve the expression problem.
- C++ has got it right straight away and work has been done to improve parametric polymorphism to allow for ergonomic higher kinded types (generic types that themselves accept type variables).
- Further work is required to further improve expressiveness and ergonomics of languages with type systems.
- Most of languages with type systems lack scalable ways to deal with heterogenous data.
- Structure-aware features…
TL;DR
- Computer programmers expect their language environments to reject bad programs. It’s largely done with lightweight formal methods.
- Runtime monitoring (the thing that tells you that
undefined is not a funciton) is an example of such a formal method. - A type system is also an example of such a formal method.
- Type systems target a range of properties deemed as “bad”, for which it is guaranteed that programs having those are rejected.
- This may and does result in “good” programs having “bad” properties being rejected. We say that it means that type systems limit expresiveness of a language.
- “If it compiles…
Published on Fri, Apr 09, 2021, by doma team, working from Bristol, UK.
TL;DR
When to resort to shell scripts:
- Portability is important
- Problem at hand is compact
- File system interaction
- Command-line program automation
When to search for an alternative
- Extensibility is required
- Coding mission-critical stuff
Shell scripting is dangerous, use shellcheck and limit yourself in idioms used
Computer consoles are the second most important UX improvement in computing, surpassed only by window managers. Consoles went a long way from allowing the computer user to enter programs to be executed by a single-process operating system to converting them into toolboxes. …
Published on Tue, Mar 30, 2021 by doma team, working from Bristol, UK.
TL;DR
- Don’t use regular expressions for parsing
- Parser combinators are a way to construct composable computations with higher-order functions
- Parser combinators are easy to use to get results quickly
- They are sufficient for 99% of pragmatic uses, falling short only if your library’s sole purpose is parsing
Role of parsing in computing
Data processing is a pillar of computing. To run an algorithm, one must first build up some data structures in memory. The way to populate data structures is to get some raw data and load it into memory. Data scientists work…
TL;DR
Rust
- Rust is an imperative language that has the most pattern-related language facilities
- Rust has both shallow destructuring and deep destructuring
if letmatching form can be utilised to alleviate Rust’s lack of multiple-head functions
JavaScript
- JavaScript has a lot of pattern-related language features:
- Position-based destructuring for arrays and key-based for objects
- Rest parameters, destructuring support
- Shallow-copy spread operator
- With support from Microsoft, Facebook and NPM, proper pattern-matching in JS is inevitable
Python and C++
- Language support for pattern-matching included in alpha (Edit thanks to reddit).
- Supports packing/unpacking
- C++ has powerful libraries for pattern matching. Language support is likely in C++23
All the time, ideas…
From CSV to XML to JSON, humans sure love their structured data. Computers like it too. If you think about it, X86 assembly is not much more than a structured data format. So is true for ELF, dwarf, protobuf…
PNGs, JPEGs and even MySQL database files are all structured binary formats. They can get corrupted, store hidden data or you might need to simply patch something inside without pulling heavy tools to work with a particular file format.
To explore a binary file at a glance, we suggest using
hexdump -Cto get classical side by side view of address…
