yaml-reference-parser-clj

Pure Clojure YAML 1.2 reference parser, packaged for Maven/Clojars as:

org.yamlstar/yaml-parser {:mvn/version "0.2.0"}

Leiningen:

[org.yamlstar/yaml-parser "0.2.0"]

Usage

(require '[yaml-parser.core :as yaml-parser])

(yaml-parser/parse "name: YAML\nitems: [1, 2]\n")

The parser returns YAML event maps such as stream_start, document_start, mapping_start, scalar, and stream_end.

Performance

The grammar is generated directly from the machine-readable YAML 1.2 spec and keeps its ordered-choice structure for spec parity. The engine makes that fast with packrat memoization of the flow-context rules, so the backtracking that is inherent to the spec grammar costs a table lookup instead of a re-parse. Set YAML_PARSER_NO_MEMO=1 to disable memoization (useful for A/B verification that event streams are identical). bench/run-bench times the parser over a small synthetic corpus.

Development

make deps
make grammar
make test
make jar
VERSION=0.2.0 make deploy

The Makefile uses https://github.com/makeplus/makes to install local bb, clojure, lein, maven, and perl tools under .cache/local. make test runs both focused API tests and the upstream yaml-test-suite TAP runner. make deploy publishes to Clojars through deps-deploy; make deploy-lein uses Leiningen.