Returns false if there are no uses.

@return bool
493773
protected function areRequirementsMet(): bool
    {
        return (bool) $this->uses = ClassHelper::getTraitUsePointers($this->getFile(), $this->getStackPos());
    }
738045
public function IsNotFoundDispatched () {
		$toolClass = $this->toolClass;
		$defaultCtrlName = $toolClass::GetDashedFromPascalCase($this->defaultControllerName);
		$errorActionName = $toolClass::GetDashedFromPascalCase($this->defaultControllerNotFoundActionName);
		return $this->request->GetControllerName() == $defaultCtrlName &&
			$this->request->GetActionName() == $errorActionName;
	}
278583
public function isEmpty()
    {
        if ($this->getStorage()->isEmpty()) {
            return true;
        }
        $identity = $this->getStorage()->read();
        if ($identity === null) {
            $this->clear();
            return true;
        }

        return false;
    }
242835
public function prune() {
		if ( ! $this->enabled ) {
			return false;
		}

		/** @var Finder $finder */
		$finder = $this->get_finder()->sortByName();

		$files_to_delete = array();

		foreach ( $finder as $file ) {
			$pieces    = explode( '-', $file->getBasename( $file->getExtension() ) );
			$timestamp = end( $pieces );

			// No way to compare versions, do nothing.
			if ( ! is_numeric( $timestamp ) ) {
				continue;
			}

			$basename_without_timestamp = str_replace( '-' . $timestamp, '', $file->getBasename() );

			// There's a file with an older timestamp, delete it.
			if ( isset( $files_to_delete[ $basename_without_timestamp ] ) ) {
				unlink( $files_to_delete[ $basename_without_timestamp ] );
			}

			$files_to_delete[ $basename_without_timestamp ] = $file->getRealPath();
		}

		return true;
	}
804470
public function is()
    {
        $patterns = func_get_args();

        $name = $this->currentRouteName();

        foreach ($patterns as $pattern) {
            if (Str::is($pattern, $this->currentRouteName())) {
                return true;
            }
        }

        return false;
    }
346085
public function hasSharedParent()
    {
        $parent = $this->getParent();

        if ($parent != null && ($parent->isShared() || $parent->hasSharedParent())) {
            return true;
        }

        return false;
    }
384874
public function isSuspended()
	{
		if ($this->suspended and $this->suspended_at)
		{
			$this->removeSuspensionIfAllowed();
			return (bool) $this->suspended;
		}

		return false;
	}
74605
public function isEmpty() {

        // return true if all properties are null
        return (is_null($this->name) && is_null($this->ANSICode) && is_null($this->XTermCode) && is_null($this->RGB));

    }
227556
function MustUseCache()
    {
        if ($this->cacheLifetime == 0)
        {
            return false;
        }
        if (!File::Exists($this->file))
        {
            return false;
        }
        $now = Date::Now();
        $lastMod = File::GetLastModified($this->file);
        if ($now->TimeStamp() - $lastMod->TimeStamp() < $this->cacheLifetime)
        {
            return true;
        }
        return false;
    }
739366
protected function useCache()
    {
        // Should we use a cached version?
        if ($this->cache && $this->cacheExists()) {
            $this->templateOutput = $this->getCache();
            if ($this->templateOutput !== false) {
                return true;
            }
        }
        return false;
    }
417359
public function valid()
    {
        if ($this->_useBuffering) {
            $valid = $this->_index < $this->_count;
            if ($valid && $this->_results[$this->_index] !== null) {
                $this->_current = $this->_results[$this->_index];

                return true;
            }
            if (!$valid) {
                return $valid;
            }
        }

        $this->_current = $this->_fetchResult();
        $valid = $this->_current !== false;

        if ($valid && $this->_useBuffering) {
            $this->_results[$this->_index] = $this->_current;
        }
        if (!$valid && $this->_statement !== null) {
            $this->_statement->closeCursor();
        }

        return $valid;
    }
927455
public function hasCycle()
	{
		if( $this->hasLoop() )
			return true;
		else
		{
			foreach( $this->getNodes() as $node )
				if( $this->isPath($node, $node ) )
					return true;
		}
		return false;
	}
787213
public function is_used() {
        global $DB;
        global $CFG;

        // count grade items excluding the
        $params = array($this->id);
        $sql = "SELECT COUNT(id) FROM {grade_items} WHERE scaleid = ? AND outcomeid IS NULL";
        if ($DB->count_records_sql($sql, $params)) {
            return true;
        }

        // count outcomes
        $sql = "SELECT COUNT(id) FROM {grade_outcomes} WHERE scaleid = ?";
        if ($DB->count_records_sql($sql, $params)) {
            return true;
        }

        // Ask the competency subsystem.
        if (\core_competency\api::is_scale_used_anywhere($this->id)) {
            return true;
        }

        // Ask all plugins if the scale is used anywhere.
        $pluginsfunction = get_plugins_with_function('scale_used_anywhere');
        foreach ($pluginsfunction as $plugintype => $plugins) {
            foreach ($plugins as $pluginfunction) {
                if ($pluginfunction($this->id)) {
                    return true;
                }
            }
        }

        return false;
    }
961011
public function hasObj()
    {
        if ($this->obj === null) {
            try {
                $this->obj();
            } catch (InvalidArgumentException $e) {
                return false;
            }
        }

        return !empty($this->obj);
    }
1202305
public function isValid ()
    {
        return !$this->isEmpty() && !Helper::some($this->getFields(), function (Field $field) { return $field->isEmpty(); });
    }
467274
private function usesSoftDeletes()
    {
        return (
            (isset($this->forceDeleting) && ! $this->forceDeleting) ||
            (isset($this->softDelete) && ! $this->softDelete)
        );
    }
998986
public function isCurrent()
    {
        if (AVUser::getCurrentUser() && $this->getObjectId())
        {
            if ($this->getObjectId() == AVUser::getCurrentUser()->getObjectId())
            {
                return true;
            }
        }

        return false;
    }