8.117 Opcode

Permits defining an operator mask so that any code containing a masked opcode will not compile or execute when Perl next compiles any code. Not usually used directly; for examples of Opcode's use, see the ops pragma and the Safe module.

Valid opcodes are listed in the array op_name in the file opcode.h . Many Opcode functions and methods take lists of operators, which are composed of elements. Each element can be a:

name ( opname ) or negated name

Name of operator, usually lowercase. Prefixing the name with an exclamation mark ( ! ) removes it from the accumulated set of operations.

set ( opset )

Operator set. Binary string holding a set of zero or more operators.

tag name ( optag ) or negated tag

Operator tag name; refers to groups (or sets) of operators. Begins with a colon ( : ). Negated by prefixing with an exclamation mark ( ! ). Several optags are predefined, including the following. See the manpage for the Opcode module for the opcodes included in each tag.

:base_core      :base_io        :base_loop :base_math      :base_mem       :base_orig :browse         :dangerous      :default :filesys_open   :filesys_read   :filesys_write :others         :ownprocess     :still_to_be_decided :subprocess     :sys_db