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function MONAD(modifier) {
    'use strict';

var prototype = Object.create(null);
    prototype.is_monad = true;

function unit(value) {
        var monad = Object.create(prototype);
        monad.bind = function (func, args) {
            return func.apply(
                undefined,
                [value].concat(Array.prototype.slice.apply(args || []))
            );
        };
        if (typeof modifier === 'function') {
            value = modifier(monad, value);
        }
        return monad;
    }
    unit.method = function (name, func) {
        prototype[name] = func;
        return unit;
    };
    unit.lift_value = function (name, func) {
        prototype[name] = function () {
            return this.bind(func, arguments);
        };
        return unit;
    };
    unit.lift = function (name, func) {
        prototype[name] = function () {
            var result = this.bind(func, arguments);
            return result && result.is_monad === true ? result : unit(result);
        };
        return unit;
    };
    return unit;
}

MONAD(modifier)