scontainers/dist/types/set.js

A container/collection/iterator library for JavaScript, comfortable to use, performant and versatile.

"use strict";

function _implSymbol(target, sym, value) {
  Object.defineProperty(target, sym, {
    value,
    configurable: true
  });
  return target[sym];
}

function _getSymbol(targetSymName, ...traitSets) {
  let symbol;
  traitSets.forEach(traitSet => {
    const sym = traitSet[targetSymName];

    if (typeof sym === 'symbol') {
      if (!!symbol && symbol !== sym) {
        throw new Error(`Symbol ${targetSymName} offered by multiple trait sets.`);
      }

      symbol = sym;
    }
  });

  if (!symbol) {
    throw new Error(`No trait set is providing symbol ${targetSymName}.`);
  }

  return symbol;
}

function _testTraitSet(traitSet) {
  if (!traitSet || typeof traitSet === 'boolean' || typeof traitSet === 'number' || typeof traitSet === 'string') {
    throw new Error(`${traitSet} cannot be used as a trait set.`);
  }
}

const {
  assert,
  traits,
  toStr,
  KVN
} = require('../utils.js');

_testTraitSet(traits.utils);

_testTraitSet(traits.scontainers);

_testTraitSet(traits.semantics);

const _implTraits = _getSymbol("implTraits", traits.utils, traits.scontainers, traits.semantics);

const _values = _getSymbol("values", traits.utils, traits.scontainers, traits.semantics);

const _forEach = _getSymbol("forEach", traits.utils, traits.scontainers, traits.semantics);

const _describeScontainer = _getSymbol("describeScontainer", traits.utils, traits.scontainers, traits.semantics);

const _implCoreTraits = _getSymbol("implCoreTraits", traits.utils, traits.scontainers, traits.semantics);

const _map = _getSymbol("map", traits.utils, traits.scontainers, traits.semantics);

const _collect = _getSymbol("collect", traits.utils, traits.scontainers, traits.semantics);

traits.scontainers[_implTraits](Set, {
  from(collection) {
    if (collection[_values]) {
      return Set.from(collection[_values]());
    } else if (collection[_forEach]) {
      const set = new Set();

      collection[_forEach](value => void set.add(value));

      return set;
    }

    assert.fail();
  }

});

Set[_describeScontainer]({
  argKeys: []
});

Set[_implCoreTraits]({
  len() {
    return this.size;
  },

  has(item) {
    return this.has(item);
  },

  add(item) {
    return this.add(item);
  },

  clear() {
    this.clear();
  },

  kvIterator() {
    return {
      it: this[Symbol.iterator](),

      next() {
        const next = this.it.next();

        if (!next.done) {
          return new KVN(undefined, next.value);
        }
      }

    };
  },

  values() {
    return this;
  },

  toString() {
    return `Set{${this[_map](value => toStr.call(value))[_collect](Array).join(', ')}}`;
  }

});