space

Appearance

json-utils ​

Canonical Import ​

fennel
(local json-utils (require :json-utils))

Source Files ​

  • assets/lua/json-utils.fnl
  • src/lua_json.cpp
  • src/lua_fs.cpp

What It Provides ​

json-utils adds small persistence helpers on top of json and fs: atomic JSON writes and deterministic JSON string generation.

API Summary ​

  • write-json!(path data [opts]) serializes data with json.dumps and writes it to path. By default it writes to path .. ".tmp" and renames the temporary file into place. Pass {:atomic? false} to write directly.
  • stable-json(value) returns deterministic compact JSON text by sorting table keys lexicographically and preserving array order.

Examples ​

fennel
(local json-utils (require :json-utils))

(json-utils.write-json! "/tmp/space-settings.json"
                        {:theme "dark" :recent ["alpha" "beta"]})

(print (json-utils.stable-json {:b 2 :a 1}))

Errors and Platform Notes ​

The module asserts that fs and json are available. Atomic writes use a sibling .tmp file and fs.rename; if the rename fails, json-utils attempts to remove the temporary file and raises an explicit error. stable-json sorts keys by their string representation, so mixed key types are deterministic but should still be chosen deliberately.

  • json for raw JSON parse and serialize operations.
  • fs for lower-level file operations and atomic replacement helpers.

Aliases and Search Terms ​

Search terms: JSON utilities, stable JSON, deterministic JSON, atomic JSON write, write-json.