@thi.ng/oquery/match.js

Datalog-inspired, optimized pattern/predicate query engine for JS objects & arrays of objects

import { isNumber } from "@thi.ng/checks/is-number";
import { isString } from "@thi.ng/checks/is-string";
import { numericOp, stringOp } from "@thi.ng/compare";
const matchStrings = (key, matches, opts) => {
  const [includes, excludes] = matches.reduce(
    (acc, x) => {
      x[0] === "!" ? acc[1].push(x.substring(1)) : acc[0].push(x);
      return acc;
    },
    [[], []]
  );
  return matchMultiple(key, includes, excludes, opts);
};
const matchMultiple = (key, includes, excludes, opts = {}) => {
  const { union = false, value: valueFn } = opts;
  return excludes.length ? {
    q: [
      key,
      (values) => {
        const $values = valueFn ? valueFn(values) : values;
        for (let x of excludes) {
          if ($values.includes(x)) return false;
        }
        let match = false;
        for (let x of includes) {
          if ($values.includes(x)) {
            match = true;
            if (union) break;
          } else if (!union) {
            match = false;
            break;
          }
        }
        return match;
      }
    ],
    opts: { cwise: false }
  } : { q: [key, includes], opts: { intersect: !union } };
};
const matchPattern = (key, expr, opts) => {
  let re;
  if (expr instanceof RegExp) {
    re = expr;
  } else {
    if (expr === "*") return { q: [key, (x) => x != null], opts };
    if (/^[<>=!]/.test(expr)) {
      const op = /^[<>=!]+/.exec(expr)[0];
      const arg = expr.substring(op.length).trim();
      const argN = parseFloat(arg);
      return matchCompare(
        key,
        op,
        isNaN(argN) ? arg : argN,
        opts
      );
    }
    re = new RegExp(expr, "i");
  }
  return {
    q: [
      key,
      (x) => (isString(x) || isNumber(x)) && re.test(String(x))
    ],
    opts
  };
};
const matchCompare = (key, op, arg, opts) => ({
  q: [key, isNumber(arg) ? numericOp(op, arg) : stringOp(op, arg)],
  opts
});
export {
  matchCompare,
  matchMultiple,
  matchPattern,
  matchStrings
};