13 items tagged “compilers”
Lark parsing library JSON tutorial (via) A very convincing tutorial for a new-to-me parsing library for Python called Lark.
The tutorial covers building a full JSON parser from scratch, which ends up being just 19 lines of grammar definition code and 15 lines for the transformer to turn that tree into the final JSON.
It then gets into the details of optimization—the default Earley algorithm is quite slow, but swapping that out for a LALR parser (a one-line change) provides a 5x speedup for this particular example. # 13th August 2023, 9:50 pm
Mapping Python to LLVM (via) Codon is a fascinating new entry in the “compile Python code to something else” world—this time targeting LLVM. Ariya Shajii describes in great detail how it pulls this off, including tricks such as transforming Python generators to LLVM coroutines. Codon doesn’t promise that all Python code will work—it’s best thought of as a Python-like language which can be used to create compiled modules which can then be imported back into regular Python projects. # 10th January 2023, 2:08 am
A CGo-free port of SQLite. Fascinating Go version of SQLite, which uses Go code that has been translated from the original SQLite C using ccgo, a package by the same author which “translates cc ASTs to Go source code”. It claims to pass the full public SQLite test suite, which is very impressive. # 30th January 2022, 10:25 pm
Writing a minimal Lua implementation with a virtual machine from scratch in Rust. Phil Eaton implements a subset of Lua in a Rust in this detailed tutorial. # 15th January 2022, 6:29 pm
Introducing stack graphs (via) GitHub launched “precise code navigation” for Python today—the first language to get support for this feature. Click on any Python symbol in GitHub’s code browsing views and a box will show you exactly where that symbol was defined—all based on static analysis by a custom parser written in Rust as opposed to executing any Python code directly. The underlying computer science uses a technique called stack graphs, based on scope graphs research from Eelco Visser’s research group at TU Delft. # 9th December 2021, 11:07 pm
lex.go in json5-go. This archived GitHub repository has a beautifully clean and clear example of a hand-written lexer in Go, for the JSON5 format (JSON + comments + multi-line strings). parser.go is worth a look too. # 19th August 2021, 8:15 pm
A hands-on introduction to static code analysis. Useful tutorial on using the Python standard library tokenize and ast modules to find specific patterns in Python source code, using the visitor pattern. # 5th May 2020, 12:15 am
A Compiler Writing Journey (via) Warren Toomey has been writing a self-compiling compiler for a subset of C, and extensively documenting every step of the journey here on GitHub. The result is an extremely high quality free textbook on compiler construction. # 8th January 2020, 3:33 am
Developing for the Apple iPhone using Flash. A brilliant feat of engineering: Adobe worked around Apple’s “no runtime allowed” rules by writing a compiler front end for LLVM that compiles ActionScript 3 to ARM assembly code, and apparently ported the regular Flash drawing APIs as well. # 5th October 2009, 9:15 pm
python4ply tutorial. python4ply is a parser for Python written in Python using the PLY toolkit, which compiles to Python bytecode using the built-in compiler module. The tutorial shows how to use it to add support for Perl-style 1_000_000 readable numbers. # 11th March 2008, 5:49 am