PHP 5.3 closure-based implementation of curry(); old implementation used as fallback for older PHP versions. Added unit tests to confirm they both work!

This commit is contained in:
Brion Vibber 2009-12-15 13:53:19 -08:00
parent 00fb5feff8
commit 0158f4f73d
3 changed files with 125 additions and 13 deletions

36
lib/curry.php Normal file
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@ -0,0 +1,36 @@
<?php
/*
* StatusNet - the distributed open-source microblogging tool
* Copyright (C) 2008, 2009, StatusNet, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* PHP 5.3 implementation of function currying, using native closures.
* On 5.2 and lower we use the fallback implementation in util.php
*
* @param callback $fn
* @param ... any remaining arguments will be appended to call-time params
* @return callback
*/
function curry($fn) {
$extra_args = func_get_args();
array_shift($extra_args);
return function() use ($fn, $extra_args) {
$args = func_get_args();
return call_user_func_array($fn,
array_merge($args, $extra_args));
};
}

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@ -523,19 +523,23 @@ function callback_helper($matches, $callback, $notice_id) {
return substr($matches[0],0,$left) . $result . substr($matches[0],$right); return substr($matches[0],0,$left) . $result . substr($matches[0],$right);
} }
function curry($fn) { if (version_compare(PHP_VERSION, '5.3.0', 'ge')) {
//TODO switch to a PHP 5.3 function closure based approach if PHP 5.3 is used // lambda implementation in a separate file; PHP 5.2 won't parse it.
$args = func_get_args(); require_once INSTALLDIR . "/lib/curry.php";
array_shift($args); } else {
$id = uniqid('_partial'); function curry($fn) {
$GLOBALS[$id] = array($fn, $args); $args = func_get_args();
return create_function('', array_shift($args);
'$args = func_get_args(); '. $id = uniqid('_partial');
'return call_user_func_array('. $GLOBALS[$id] = array($fn, $args);
'$GLOBALS["'.$id.'"][0],'. return create_function('',
'array_merge('. '$args = func_get_args(); '.
'$args,'. 'return call_user_func_array('.
'$GLOBALS["'.$id.'"][1]));'); '$GLOBALS["'.$id.'"][0],'.
'array_merge('.
'$args,'.
'$GLOBALS["'.$id.'"][1]));');
}
} }
function common_linkify($url) { function common_linkify($url) {

72
tests/CurryTest.php Normal file
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@ -0,0 +1,72 @@
<?php
if (isset($_SERVER) && array_key_exists('REQUEST_METHOD', $_SERVER)) {
print "This script must be run from the command line\n";
exit();
}
define('INSTALLDIR', realpath(dirname(__FILE__) . '/..'));
define('STATUSNET', true);
define('LACONICA', true);
require_once INSTALLDIR . '/lib/common.php';
class CurryTest extends PHPUnit_Framework_TestCase
{
/**
* @dataProvider provider
*
*/
public function testProduction($callback, $curry_params, $call_params, $expected)
{
$params = array_merge(array($callback), $curry_params);
$curried = call_user_func_array('curry', $params);
$result = call_user_func_array($curried, $call_params);
$this->assertEquals($expected, $result);
}
static public function provider()
{
$obj = new CurryTestHelperObj('oldval');
return array(array(array('CurryTest', 'callback'),
array('curried'),
array('called'),
'called|curried'),
array(array('CurryTest', 'callback'),
array('curried1', 'curried2'),
array('called1', 'called2'),
'called1|called2|curried1|curried2'),
array(array('CurryTest', 'callbackObj'),
array($obj),
array('newval1'),
'oldval|newval1'),
// Confirm object identity is retained...
array(array('CurryTest', 'callbackObj'),
array($obj),
array('newval2'),
'newval1|newval2'));
}
static function callback()
{
$args = func_get_args();
return implode("|", $args);
}
static function callbackObj($val, $obj)
{
$old = $obj->val;
$obj->val = $val;
return "$old|$val";
}
}
class CurryTestHelperObj
{
public $val='';
function __construct($val)
{
$this->val = $val;
}
}