This distribution of Safe includes the Opcode module and ops pragma. The Opcode module provides functions for the manipulation of sets of perl opcodes, including the ability to mask (disable) sets of opcodes. An 'ops' pragma is provided to allow you to easily disable opcodes on the command line, e.g., $ perl -Mops=:default ... $ perl -M-ops=const -e 1 constant item trapped by operation mask at -e line 1. This code could be regarded as beta release but the definition of the optags is not stable and should not be relied upon. Comments welcome. Recent major changes to Opcode: ops_to_opset() renamed to opset(). verify_opset() added. Updated pod text to be more complete and accurate. Added notes about using bit vector ops on opsets. Moved some opcodes around within optags. Added some optags including :browse. Enhanced test suite. Recent major changes to Safe: Fixed warnings/core dumps from $safe->erase. $safe->erase now also reshares *_. Moved implementation over to use Opcode. Greatly enhanced test suite. To do: Safe pod text needs updating. Ponder removal of (undocumented) share tracking functionality.