Proven Expertise
Our team brings years of experience in the digital payments industry to provide reliable services.
<?php
/*
* Copyright 2012 Johannes M. Schmitt <schmittjoh@gmail.com>
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
namespace PhpOption;
use ArrayAccess;
use IteratorAggregate;
/**
* @template T
*
* @implements IteratorAggregate<T>
*/
abstract class Option implements IteratorAggregate
{
/**
* Creates an option given a return value.
*
* This is intended for consuming existing APIs and allows you to easily
* convert them to an option. By default, we treat ``null`` as the None
* case, and everything else as Some.
*
* @template S
*
* @param S $value The actual return value.
* @param S $noneValue The value which should be considered "None"; null by
* default.
*
* @return Option<S>
*/
public static function fromValue($value, $noneValue = null)
{
if ($value === $noneValue) {
return None::create();
}
return new Some($value);
}
/**
* Creates an option from an array's value.
*
* If the key does not exist in the array, the array is not actually an
* array, or the array's value at the given key is null, None is returned.
* Otherwise, Some is returned wrapping the value at the given key.
*
* @template S
*
* @param array<string|int,S>|ArrayAccess<string|int,S>|null $array A potential array or \ArrayAccess value.
* @param string $key The key to check.
*
* @return Option<S>
*/
public static function fromArraysValue($array, $key)
{
if (!(is_array($array) || $array instanceof ArrayAccess) || !isset($array[$key])) {
return None::create();
}
return new Some($array[$key]);
}
/**
* Creates a lazy-option with the given callback.
*
* This is also a helper constructor for lazy-consuming existing APIs where
* the return value is not yet an option. By default, we treat ``null`` as
* None case, and everything else as Some.
*
* @template S
*
* @param callable $callback The callback to evaluate.
* @param array $arguments The arguments for the callback.
* @param S $noneValue The value which should be considered "None";
* null by default.
*
* @return LazyOption<S>
*/
public static function fromReturn($callback, array $arguments = [], $noneValue = null)
{
return new LazyOption(static function () use ($callback, $arguments, $noneValue) {
/** @var mixed */
$return = call_user_func_array($callback, $arguments);
if ($return === $noneValue) {
return None::create();
}
return new Some($return);
});
}
/**
* Option factory, which creates new option based on passed value.
*
* If value is already an option, it simply returns. If value is callable,
* LazyOption with passed callback created and returned. If Option
* returned from callback, it returns directly. On other case value passed
* to Option::fromValue() method.
*
* @template S
*
* @param Option<S>|callable|S $value
* @param S $noneValue Used when $value is mixed or
* callable, for None-check.
*
* @return Option<S>|LazyOption<S>
*/
public static function ensure($value, $noneValue = null)
{
if ($value instanceof self) {
return $value;
} elseif (is_callable($value)) {
return new LazyOption(static function () use ($value, $noneValue) {
/** @var mixed */
$return = $value();
if ($return instanceof self) {
return $return;
} else {
return self::fromValue($return, $noneValue);
}
});
} else {
return self::fromValue($value, $noneValue);
}
}
/**
* Lift a function so that it accepts Option as parameters.
*
* We return a new closure that wraps the original callback. If any of the
* parameters passed to the lifted function is empty, the function will
* return a value of None. Otherwise, we will pass all parameters to the
* original callback and return the value inside a new Option, unless an
* Option is returned from the function, in which case, we use that.
*
* @template S
*
* @param callable $callback
* @param mixed $noneValue
*
* @return callable
*/
public static function lift($callback, $noneValue = null)
{
return static function () use ($callback, $noneValue) {
/** @var array<int, mixed> */
$args = func_get_args();
$reduced_args = array_reduce(
$args,
/** @param bool $status */
static function ($status, self $o) {
return $o->isEmpty() ? true : $status;
},
false
);
// if at least one parameter is empty, return None
if ($reduced_args) {
return None::create();
}
$args = array_map(
/** @return T */
static function (self $o) {
// it is safe to do so because the fold above checked
// that all arguments are of type Some
/** @var T */
return $o->get();
},
$args
);
return self::ensure(call_user_func_array($callback, $args), $noneValue);
};
}
/**
* Returns the value if available, or throws an exception otherwise.
*
* @throws \RuntimeException If value is not available.
*
* @return T
*/
abstract public function get();
/**
* Returns the value if available, or the default value if not.
*
* @template S
*
* @param S $default
*
* @return T|S
*/
abstract public function getOrElse($default);
/**
* Returns the value if available, or the results of the callable.
*
* This is preferable over ``getOrElse`` if the computation of the default
* value is expensive.
*
* @template S
*
* @param callable():S $callable
*
* @return T|S
*/
abstract public function getOrCall($callable);
/**
* Returns the value if available, or throws the passed exception.
*
* @param \Exception $ex
*
* @return T
*/
abstract public function getOrThrow(\Exception $ex);
/**
* Returns true if no value is available, false otherwise.
*
* @return bool
*/
abstract public function isEmpty();
/**
* Returns true if a value is available, false otherwise.
*
* @return bool
*/
abstract public function isDefined();
/**
* Returns this option if non-empty, or the passed option otherwise.
*
* This can be used to try multiple alternatives, and is especially useful
* with lazy evaluating options:
*
* ```php
* $repo->findSomething()
* ->orElse(new LazyOption(array($repo, 'findSomethingElse')))
* ->orElse(new LazyOption(array($repo, 'createSomething')));
* ```
*
* @param Option<T> $else
*
* @return Option<T>
*/
abstract public function orElse(self $else);
/**
* This is similar to map() below except that the return value has no meaning;
* the passed callable is simply executed if the option is non-empty, and
* ignored if the option is empty.
*
* In all cases, the return value of the callable is discarded.
*
* ```php
* $comment->getMaybeFile()->ifDefined(function($file) {
* // Do something with $file here.
* });
* ```
*
* If you're looking for something like ``ifEmpty``, you can use ``getOrCall``
* and ``getOrElse`` in these cases.
*
* @deprecated Use forAll() instead.
*
* @param callable(T):mixed $callable
*
* @return void
*/
abstract public function ifDefined($callable);
/**
* This is similar to map() except that the return value of the callable has no meaning.
*
* The passed callable is simply executed if the option is non-empty, and ignored if the
* option is empty. This method is preferred for callables with side-effects, while map()
* is intended for callables without side-effects.
*
* @param callable(T):mixed $callable
*
* @return Option<T>
*/
abstract public function forAll($callable);
/**
* Applies the callable to the value of the option if it is non-empty,
* and returns the return value of the callable wrapped in Some().
*
* If the option is empty, then the callable is not applied.
*
* ```php
* (new Some("foo"))->map('strtoupper')->get(); // "FOO"
* ```
*
* @template S
*
* @param callable(T):S $callable
*
* @return Option<S>
*/
abstract public function map($callable);
/**
* Applies the callable to the value of the option if it is non-empty, and
* returns the return value of the callable directly.
*
* In contrast to ``map``, the return value of the callable is expected to
* be an Option itself; it is not automatically wrapped in Some().
*
* @template S
*
* @param callable(T):Option<S> $callable must return an Option
*
* @return Option<S>
*/
abstract public function flatMap($callable);
/**
* If the option is empty, it is returned immediately without applying the callable.
*
* If the option is non-empty, the callable is applied, and if it returns true,
* the option itself is returned; otherwise, None is returned.
*
* @param callable(T):bool $callable
*
* @return Option<T>
*/
abstract public function filter($callable);
/**
* If the option is empty, it is returned immediately without applying the callable.
*
* If the option is non-empty, the callable is applied, and if it returns false,
* the option itself is returned; otherwise, None is returned.
*
* @param callable(T):bool $callable
*
* @return Option<T>
*/
abstract public function filterNot($callable);
/**
* If the option is empty, it is returned immediately.
*
* If the option is non-empty, and its value does not equal the passed value
* (via a shallow comparison ===), then None is returned. Otherwise, the
* Option is returned.
*
* In other words, this will filter all but the passed value.
*
* @param T $value
*
* @return Option<T>
*/
abstract public function select($value);
/**
* If the option is empty, it is returned immediately.
*
* If the option is non-empty, and its value does equal the passed value (via
* a shallow comparison ===), then None is returned; otherwise, the Option is
* returned.
*
* In other words, this will let all values through except the passed value.
*
* @param T $value
*
* @return Option<T>
*/
abstract public function reject($value);
/**
* Binary operator for the initial value and the option's value.
*
* If empty, the initial value is returned. If non-empty, the callable
* receives the initial value and the option's value as arguments.
*
* ```php
*
* $some = new Some(5);
* $none = None::create();
* $result = $some->foldLeft(1, function($a, $b) { return $a + $b; }); // int(6)
* $result = $none->foldLeft(1, function($a, $b) { return $a + $b; }); // int(1)
*
* // This can be used instead of something like the following:
* $option = Option::fromValue($integerOrNull);
* $result = 1;
* if ( ! $option->isEmpty()) {
* $result += $option->get();
* }
* ```
*
* @template S
*
* @param S $initialValue
* @param callable(S, T):S $callable
*
* @return S
*/
abstract public function foldLeft($initialValue, $callable);
/**
* foldLeft() but with reversed arguments for the callable.
*
* @template S
*
* @param S $initialValue
* @param callable(T, S):S $callable
*
* @return S
*/
abstract public function foldRight($initialValue, $callable);
}
How it Works
Getting started with NFC Pay is simple and quick. Register your account, add your cards, and you're ready to make payments in no time. Whether you're paying at a store, sending money to a friend, or managing your merchant transactions, NFC Pay makes it easy and secure.
Download the NFC Pay app and sign up with your email or phone number. Complete the registration process by verifying your identity, and set up your secure PIN to protect your account.
Link your debit or credit cards to your NFC Pay wallet. Simply scan your card or enter the details manually, and you’re set to load funds, shop, and pay with ease.
To pay, simply tap your phone or scan the QR code at checkout. You can also transfer money to other users with a few taps. Enjoy fast, contactless payments with top-notch security.
Security System
NFC Pay prioritizes your security with advanced features that safeguard every transaction. From SMS or email verification to end-to-end encryption, we've implemented robust measures to ensure your data is always protected. Our security systems are designed to prevent unauthorized access and provide you with a safe and reliable payment experience.
Receive instant alerts for every transaction to keep track of your account activities.
Verify your identity through our Know Your Customer process to prevent fraud and enhance security.
Dramatically supply transparent backward deliverables before caward comp internal or "organic" sources.
All your data and transactions are encrypted, ensuring that your sensitive information remains private.
Monitor unusual activity patterns to detect and prevent suspicious behavior in real-time.
Why Choice Us
With NFC Pay, you get a trusted platform backed by proven expertise and a commitment to quality. We put our customers first, offering innovative solutions tailored to your needs, ensuring every transaction is secure, swift, and seamless.
Our team brings years of experience in the digital payments industry to provide reliable services.
We prioritize excellence, ensuring that every aspect of our platform meets the highest standards.
Your needs drive our solutions, and we are dedicated to delivering a superior user experience.
We continuously evolve, integrating the latest technologies to enhance your payment experience.
Testimonial Section
Hear from our users who trust NFC Pay for their everyday transactions. Our commitment to security, ease of use, and exceptional service shines through in their experiences. See why our clients choose NFC Pay for their payment needs and how it has transformed the way they manage their finances.
App Section
Unlock the full potential of NFC Pay by downloading our app, designed to bring secure, swift, and smart transactions to your fingertips. Whether you're paying at a store, transferring money to friends, or managing your business payments, the NFC Pay app makes it effortless. Available on both iOS and Android, it's your all-in-one solution for convenient and reliable digital payments. Download now and experience the future of payments!