--TEST--
PHP Spec test generated from ./expressions/yield_operator/yield.php
--FILE--
<?php

/*
   +-------------------------------------------------------------+
   | Copyright (c) 2014 Facebook, Inc. (http://www.facebook.com) |
   +-------------------------------------------------------------+
*/

error_reporting(-1);

// define a simple generator that returns a series of consecutive values

function series($start, $end)
{
	for ($i = $start; $i <= $end; ++$i)
	{
		yield $i;
	}
}

///*
foreach (series(1, 5) as $key => $val)
{
	echo "key: $key, value: $val\n";
}

echo "===========================\n";

foreach (series('d', 'f') as $key => $val)
{
	echo "key: $key, value: $val\n";
}
//*/

///*

// Just what does a function generator return?

echo "===========================\n";
$a = series(5, 15);
var_dump($a);   // PHP5 and HHVM: type Generator
                // HHVM is also: type Continuation
echo "This type " . (($a instanceof Generator)
                     ? "is"
                     : "is not")
                  . " an instance of Generator\n";

// $serialString = serialize($a);	// Uncaught exception

echo "===========================\n";
//*/

///*
// define a generator that returns sucessive lines from a file of text

function getTextFileLines($filename)
{
	$infile = fopen($filename, 'r');
	if ($infile == FALSE)
	{
		// handle file-open failure
	}

	try
	{
		while ($textLine = fgets($infile))	// while not EOF
		{
//			echo "len before rtrim: " . + strlen($textLine) . "\n";
			$textLine = rtrim($textLine, "\r\n");	// strip off line terminator
//			echo "len after rtrim:  " . + strlen($textLine) . "\n";
			yield $textLine;
        }
    }
    finally
	{
		fclose($infile);
	}
}

foreach (getTextFileLines(__DIR__."/Testfile.txt") as $line)
{
	echo ">$line<\n";
}
echo "===========================\n";
//*/

///*
// See if return is allowed in any form in a generator function
// also yield on its own + yield in an expression

function f()
{
//	if (0)		// even if the yield is never executed, can't have return with value
	for ($i = 1; $i <= 3; ++$i)
	{
//		yield;				// PHP5: uses next-available int key and value NULL
							// HHVM: Fatal error: syntax error, unexpected ';'
		yield $i;
//		return;
//		return NULL;
//		$x = (yield $i);	// PHP5: yield produces a NULL result
							// HHVM: Fatal error: syntax error, unexpected T_YIELD
//		var_dump($x);
	}
//	return;			// PHP5: OK
					// HHVM: Fatal error: Cannot mix 'return' and 'yield' in the same function
//	return NULL;	// PHP5: OK; it is like return;, which returns NULL implicitly
					// HHVM: Fatal error: Cannot mix 'return' and 'yield' in the same function
	$n = NULL;
//	return $n;		// error: Generators cannot return values using "return"
//	return 0;		// error: Generators cannot return values using "return"
}

foreach (f() as $key => $val)
{
	echo "key: $key, value: $val\n";
}
echo "===========================\n";
//*/

///*
// define a simple generator that returns key/value pairs

function series2($start, $end, $keyPrefix = "")
{
	for ($i = $start; $i <= $end; ++$i)
	{
//		yield;							// default key is int 0,1,2... and value NULL
		yield $keyPrefix . $i => $i;	// specify a key/value pair
//		$x = (yield $keyPrefix . $i => $i);	// PHP5: yield produces a NULL result
										// HHVM: Fatal error: syntax error, unexpected T_YIELD
//		var_dump($x);
	}
}

foreach (series2(1, 5, "X") as $key => $val)
{
	echo "key: $key, value: $val\n";
//	echo ($val == NULL) ? "value is NULL\n" : "value is not NULL\n";
}

echo "===========================\n";

foreach (series2('d', 'f', "Key") as $key => $val)
{
	echo "key: $key, value: $val\n";
}
//*/
--EXPECT--
key: 0, value: 1
key: 1, value: 2
key: 2, value: 3
key: 3, value: 4
key: 4, value: 5
===========================
key: 0, value: d
key: 1, value: e
key: 2, value: f
===========================
object(Generator)#1 (0) {
}
This type is an instance of Generator
===========================
>Once upon a time,<
>in a land<
>far,   <
>far away,  <
>there lived an ogre called Big Bad Bruce.<
===========================
key: 0, value: 1
key: 1, value: 2
key: 2, value: 3
===========================
key: X1, value: 1
key: X2, value: 2
key: X3, value: 3
key: X4, value: 4
key: X5, value: 5
===========================
key: Keyd, value: d
key: Keye, value: e
key: Keyf, value: f