polylabel 0.1.11

A Rust implementation of the Polylabel algorithm
Documentation 
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'use strict';

module.exports = TinyQueue;

function TinyQueue(data, compare) {
    if (!(this instanceof TinyQueue)) return new TinyQueue(data, compare);

    this.data = data || [];
    this.length = this.data.length;
    this.compare = compare || defaultCompare;

    if (data) for (var i = Math.floor(this.length / 2); i >= 0; i--) this._down(i);
}

function defaultCompare(a, b) {
    return a < b ? -1 : a > b ? 1 : 0;
}

TinyQueue.prototype = {

    push: function (item) {
        this.data.push(item);
        this.length++;
        this._up(this.length - 1);
    },

    pop: function () {
        var top = this.data[0];
        this.data[0] = this.data[this.length - 1];
        this.length--;
        this.data.pop();
        this._down(0);
        return top;
    },

    peek: function () {
        return this.data[0];
    },

    _up: function (pos) {
        var data = this.data,
            compare = this.compare;

        while (pos > 0) {
            var parent = Math.floor((pos - 1) / 2);
            if (compare(data[pos], data[parent]) < 0) {
                swap(data, parent, pos);
                pos = parent;

            } else break;
        }
    },

    _down: function (pos) {
        var data = this.data,
            compare = this.compare,
            len = this.length;

        while (true) {
            var left = 2 * pos + 1,
                right = left + 1,
                min = pos;

            if (left < len && compare(data[left], data[min]) < 0) min = left;
            if (right < len && compare(data[right], data[min]) < 0) min = right;

            if (min === pos) return;

            swap(data, min, pos);
            pos = min;
        }
    }
};

function swap(data, i, j) {
    var tmp = data[i];
    data[i] = data[j];
    data[j] = tmp;
}