HsYAML

HsYAML is a YAML 1.2 processor, i.e. a library for parsing and serializing YAML documents.

Features of HsYAML include:

Pure Haskell implementation with small dependency footprint and emphasis on strict compliance with the YAML 1.2 specification. Direct decoding to native Haskell types via (aeson-inspired) typeclass-based API (see Data.YAML). Allows round-tripping while preserving ordering, anchors, and comments at Event-level. Support for constructing custom YAML node graph representation (including support for cyclic YAML data structures). Support for the standard (untyped) Failsafe, (strict) JSON, and (flexible) Core "schemas" providing implicit typing rules as defined in the YAML 1.2 specification (including support for user-defined custom schemas; see Data.YAML.Schema). Support for emitting YAML using Failsafe, (strict) JSON, and (flexible) Core "schemas" (including support for user-defined custom encoding schemas; see Data.YAML.Schema). Event-based API resembling LibYAML's Event-based API (see Data.YAML.Event). Low-level API access to lexical token-based scanner (see Data.YAML.Token).

See also the HsYAML-aeson package which allows to decode and encode YAML by leveraging aeson's FromJSON and ToJSON instances.