Nim implementation of the Preserves data language
Use set[T] rather than HashSet[T] for enum sets
Use BiggestInt in generated code
Add apply procedure



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Nim implementation of the Preserves data language.


To parse or produce Preserves one should write a schema and generate a Nim module using the preserves_schema_nim utility. This module will contain Nim types corresponding to schema definitions. The toPreserve andfromPreserve routines will convert Nim types to and from Preserves. The decodePreserves, parsePreserves, encode, and $ routines will convert Preserve objects to and from binary and textual encoding.

To debug the toPreserves and fromPreserves routines compile with -d:tracePreserves.


  • preserves_schema_nim
  • preserves_encode
  • preserves_decode
  • preserves_from_json
  • preserves_to_json


preserves_encode is a multi-call binary that implements preserves_encode, preserves_decode, preserves_from_json, and preserves_to_json, so the appropriate symlinks should be created during packaging.