JJPWRGEM

JJPWRGEM JSON Parser With Really Good Error Messages

An RFC 8259 compliant JSON language server and formatter!

$ echo -en "{\"coolKey\"}" | jjp check
error: expected colon after key, found `}`
 --> stdin:1:11
  |
1 | {"coolKey"}
  |  ---------^
  |  |
  |  expected due to `"coolKey"`
  |
help: insert colon and placeholder value
  |
1 | {"coolKey": "🐟🛹"}
  |           ++++++++

Why JJP?

• Rich errors with context, descriptions, and patches
• Diagnostics are calculated 2–3x faster and use 6–10x less RAM than VSCode's LSP
• Parses and pretty prints a 1.7MB file in ~11ms — benchmarks

Also there's a really cool axolotl riding a skateboard as the logo

Installation

Precompiled

Precompiled x86-64 binaries require a CPU with AVX2 support (Intel Haswell 2013+, AMD Ryzen 2017+). ARM binaries have no special requirements

mise use -g github:20jasper/jjpwrgem

See releases for shell and PowerShell installation scripts, or npm install -g jjpwrgem

From source

RUSTFLAGS="-C target-cpu=native" cargo install --path .

LSP

See LSP setup to configure your editor

Stability

Internal libraries are likely unstable. Formatting output is unstable

FAQ

What does JJPWRGEM stand for?

JJPWRGEM JSON Parser With Really Good Error Messages. I was inspired by GNU to make a recursive acronym

How do you pronounce JJPWRGEM?

/ˈdʒeɪ dʒeɪ ˈpaʊər dʒɛm/ JAY-jay-POW-er-jem

But why is it called that?

It sounds cool and the name isn't taken on any package managers

Is it blazingly fast™?

Axolotls can't walk so fast, so skateboards are pretty fast 🛹🐟

See the benchmarks

Why is the logo an axolotl riding a skateboard?

It's cool

How long is an axolotl?

According to the San Diego zoo, "[a]n axolotl can reach 12 inches in length, but on average grows to about 9 inches¹"

Footnotes

1. https://animals.sandiegozoo.org/animals/axolotl ↩