debugger invoked on a SYMBOL-PACKAGE-LOCKED-ERROR:
Lock on package SB-DEBUG violated when defining VAR as a structure.
See also:
The SBCL Manual, Node "Package Locks"
Type HELP for debugger help, or (SB-EXT:QUIT) to exit from SBCL.
restarts (invokable by number or by possibly-abbreviated name):
0: [CONTINUE ] Ignore the package lock.
1: [IGNORE-ALL ] Ignore all package locks in the context of this operation.
2: [UNLOCK-PACKAGE] Unlock the package.
3: [ABORT ] Exit debugger, returning to top level.
(PACKAGE-LOCK-VIOLATION #<PACKAGE "SB-DEBUG">)