samwilson / simple-wikidata

examples/query.php

<?php

require_once __DIR__ . '/../vendor/autoload.php';

// Any PSR6 cache can be used.
$cache = new Stash\Pool( new \Stash\Driver\FileSystem() );

$sparql = 'SELECT ?item WHERE {
  ?item wdt:P31 wd:Q54050
} LIMIT 5';
$query = new \Samwilson\SimpleWikidata\Query( $sparql, 'en', $cache );
$hills = $query->getItems();
foreach ( $hills as $hill ) {
	$heights = $hill->getPropertyOfTypeQuantity( 'P2044' );
	if ( !$heights ) {
		echo "No heights found for " . $hill->getLabel() . "\n";
		continue;
	}
	$height = array_shift( $heights );

It seems like $heights can also be of type true; however, parameter $array of array_shift() does only seem to accept array, maybe add an additional type check?

	echo $hill->getLabel() . " is "
		. $height['amount'] . " " . $height['unit']->getLabel() . " high.\n";
}