ЭЛЕКТРОННАЯ БИБЛИОТЕКА КОАПП |
Сборники Художественной, Технической, Справочной, Английской, Нормативной, Исторической, и др. литературы. |
3.2.185 useuse The use declaration imports some semantics into the current package from the named module, generally by aliasing certain subroutine or variable names into your package. It is exactly equivalent to the following: BEGIN { require The If you don't want your namespace altered, explicitly supply an empty list: use Module (); That is exactly equivalent to the following: BEGIN { require Module; } Because this is a wide-open interface, pragmas (compiler directives) are also implemented this way. Currently implemented pragmas include: use integer; use diagnostics; use sigtrap qw(SEGV BUS); use strict qw(subs vars refs); These pseudomodules typically import semantics into the current block scope, unlike ordinary modules, which import symbols into the current package. (The latter are effective through the end of the file.) There's a corresponding declaration, no, that "unimports" any meanings originally imported by use, but that have since become, er, unimportant: no integer; no strict 'refs'; See Chapter 7 for a list of standard modules and pragmas. |