Laravel错误生成缓存文件路由

Some say a closure cannot be serialize for "php artisan route:cache" command.

So, the cached file routes.php is missing. Is that a problem?

My project lives in gitlab/Graphics3D/notes/

PS C:\www
otes> C:\PHP\php.exe artisan route:cache
PHP Warning:  Module 'openssl' already loaded in Unknown on line 0

Warning: Module 'openssl' already loaded in Unknown on line 0
MIB search path: c:/usr/share/snmp/mibs
Cannot find module (IP-MIB): At line 0 in (none)
Cannot find module (IF-MIB): At line 0 in (none)
Cannot find module (TCP-MIB): At line 0 in (none)
Cannot find module (UDP-MIB): At line 0 in (none)
Cannot find module (HOST-RESOURCES-MIB): At line 0 in (none)
Cannot find module (SNMPv2-MIB): At line 0 in (none)
Cannot find module (SNMPv2-SMI): At line 0 in (none)
Cannot find module (NOTIFICATION-LOG-MIB): At line 0 in (none)
Cannot find module (UCD-SNMP-MIB): At line 0 in (none)
Cannot find module (UCD-DEMO-MIB): At line 0 in (none)
Cannot find module (SNMP-TARGET-MIB): At line 0 in (none)
Cannot find module (NET-SNMP-AGENT-MIB): At line 0 in (none)
Cannot find module (DISMAN-EVENT-MIB): At line 0 in (none)
Cannot find module (SNMP-VIEW-BASED-ACM-MIB): At line 0 in (none)
Cannot find module (SNMP-COMMUNITY-MIB): At line 0 in (none)
Cannot find module (SNMP-FRAMEWORK-MIB): At line 0 in (none)
Cannot find module (SNMP-MPD-MIB): At line 0 in (none)
Cannot find module (SNMP-USER-BASED-SM-MIB): At line 0 in (none)
Cannot find module (SNMP-NOTIFICATION-MIB): At line 0 in (none)
Cannot find module (SNMPv2-TM): At line 0 in (none)


Route cache cleared!



In Route.php line 880:

  Unable to prepare route [api/user] for serialization. Uses Closure.

So, we cannot use closure in route files? Why?