public function test_substring_between()
{
$this->assertEquals(array('[hello]', 0, 6), stack_utils::substring_between('[hello] world!', '[', ']'));
$this->assertEquals(array('[world]', 6, 12), stack_utils::substring_between('hello [world]!', '[', ']'));
$this->assertEquals(array('[world]', 8, 14), stack_utils::substring_between('[hello] [world]!', '[', ']', 8));
$this->assertEquals(array('[world]', 8, 14), stack_utils::substring_between('[hello] [world]!', '[', ']', 1));
$this->assertEquals(array('$hello$', 0, 6), stack_utils::substring_between('$hello$ world!', '$', '$'));
$this->assertEquals(array('$world$', 6, 12), stack_utils::substring_between('hello $world$!', '$', '$'));
$this->assertEquals(array('$world$', 8, 14), stack_utils::substring_between('$hello$ $world$!', '$', '$', 8));
$this->assertEquals(array('$ $', 6, 8), stack_utils::substring_between('$hello$ $world$!', '$', '$', 1));
$this->assertEquals(array('[he[ll]o]', 0, 8), stack_utils::substring_between('[he[ll]o] world!', '[', ']'));
$this->assertEquals(array('[[[]w[o]r[[l]d]]]', 6, 22), stack_utils::substring_between('hello [[[]w[o]r[[l]d]]]!', '[', ']'));
}
/**
* This function checks chained inequalities
* If we have two or more inequality symbols then we must have a logical connection {or/and} between each pair.
* First we need to split over commas to break up lists etc.
*/
private function check_chained_inequalities($ex)
{
if (substr_count($ex, '<') + substr_count($ex, '>') < 2) {
return true;
}
// Plots, and HTML elements are protected within strings when they come back through the CAS.
$found = stack_utils::substring_between($ex, '<html>', '</html>');
if ($found[1] > 0) {
$ex = str_replace($found[0], '', $ex);
}
// Separate out lists, sets, etc.
$exsplit = explode(',', $ex);
$bits = array();
$ok = true;
foreach ($exsplit as $bit) {
$ok = $ok && $this->check_chained_inequalities_ind($bit);
}
return $ok;
}
protected function unpack_helper($rawresultfragment)
{
// Take the raw string from the CAS, and unpack this into an array.
$offset = 0;
$rawresultfragmentlen = strlen($rawresultfragment);
$unparsed = '';
$errors = '';
if ($eqpos = strpos($rawresultfragment, '=', $offset)) {
// Check there are ='s.
do {
$gb = stack_utils::substring_between($rawresultfragment, '[', ']', $eqpos);
$val = substr($gb[0], 1, strlen($gb[0]) - 2);
$val = trim($val);
if (preg_match('/[-A-Za-z0-9].*/', substr($rawresultfragment, $offset, $eqpos - $offset), $regs)) {
$var = trim($regs[0]);
} else {
$var = 'errors';
$errors['LOCVARNAME'] = "Couldn't get the name of the local variable.";
}
$unparsed[$var] = $val;
$offset = $gb[2];
} while (($eqpos = strpos($rawresultfragment, '=', $offset)) && $offset < $rawresultfragmentlen);
} else {
$errors['PREPARSE'] = "There are no ='s in the raw output from the CAS!";
}
if ('' != $errors) {
$unparsed['errors'] = $errors;
}
return $unparsed;
}
