 |  |
8.167. Opcode
Permits defining an operator mask (opmask) 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 Opcode module's manpage 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
8.167.1. Functions
All the following functions can be exported.
| define_optag |
define_optag (optag, opset)
Defines optag as symbolic name for the set opset.
| empty_opset |
empty_opset
Returns an empty opset.
| full_opset |
full_opset
Returns an opset that includes all operators.
| invert_opset |
invert_opset (opset)
Returns an opset that is the inverse of opset.
| opcodes |
opcodes
In scalar context, returns the number of opcodes in this version of Perl.
| opdesc |
opdesc (op, ...)
Takes list of operator names and returns the corresponding list descriptions.
| opdump |
opdump ([pat])
Writes two-column list of operator names and descriptions to STDOUT. If pat is specified, only lines matching the (case-insensitive) pattern are output.
| opmask |
opmask
Returns an opset corresponding to the current opmask.
| opmask_add |
opmask_add (opset)
Adds opset to the current opmask.
| opset |
opset (op, ...)
Returns an opset containing the listed operators.
| opset_to_hex |
opset_to_hex (opset)
Returns string representation of opset.
| opset_to_ops |
opset_to_ops (opset)
Returns list of operator names corresponding to the operators in the set opset.
| verify_opset |
verify_opset (opset[, ...])
Returns true if opset appears to be a valid opset, else returns false. croak s instead of returning false if optional second parameter is true.
|  | |
| 8.166. ODBM_File |  | 8.168. ops |
Copyright © 2002 O'Reilly & Associates. All rights reserved.