v9.1.0

New S.unnest helper

S.t<'value> => S.t<array<'value>>

let schema = S.unnest(S.schema(s => {
  id: s.matches(S.string),
  name: s.matches(S.null(S.string)),
  deleted: s.matches(S.bool),
}))

[{id: "0", name: Some("Hello"), deleted: false}, {id: "1", name: None, deleted: true}]->S.reverseConvertOrThrow(schema)
// [["0", "1"], ["Hello", null], [false, true]]

The helper function is inspired by the article Boosting Postgres INSERT Performance by 2x With UNNEST. It allows you to flatten a nested array of objects into arrays of values by field.

The main concern of the approach described in the article is usability. And ReScript Schema completely solves the problem, providing a simple and intuitive API that is even more performant than S.array.

Checkout the compiled code yourself:

(i) => {
  let v1 = [new Array(i.length), new Array(i.length), new Array(i.length)];
  for (let v0 = 0; v0 < i.length; ++v0) {
    let v3 = i[v0];
    try {
      let v4 = v3["name"],
        v5;
      if (v4 !== void 0) {
        v5 = v4;
      } else {
        v5 = null;
      }
      v1[0][v0] = v3["id"];
      v1[1][v0] = v5;
      v1[2][v0] = v3["deleted"];
    } catch (v2) {
      if (v2 && v2.s === s) {
        v2.path = "" + "[\"'+v0+'\"]" + v2.path;
      }
      throw v2;
    }
  }
  return v1;
};

Other changes

• Improved S.array performance
• Fixed reverse operations for S.schema used inside of the s.flatten

Full Changelog: v9.0.1...v9.1.0