| Name : perl-Tie-OneOff
| |
| Version : 1.03
| Vendor : obs://build_opensuse_org/devel:languages:perl
|
| Release : lp155.6.1
| Date : 2023-07-20 19:31:47
|
| Group : Development/Libraries/Perl
| Source RPM : perl-Tie-OneOff-1.03-lp155.6.1.src.rpm
|
| Size : 0.01 MB
| |
| Packager : https://www_suse_com/
| |
| Summary : create tied variables without defining a separate package
|
Description :
The Perl tie mechanism ties a Perl variable to a Perl object. This means
that, conventionally, for each distinct set of tied variable semantics one
needs to create a new package. The package symbol table then acts as a
dispatch table for the intrinsic actions (such as \'FETCH\', \'STORE\',
\'FETCHSIZE\') that can be performed on Perl variables.
Sometimes it would seem more natural to associate a dispatch table hash
directly with the variable and pretend as if the intermediate object did
not exist. This is what \'Tie::OneOff\' does.
It is important to note that in this model there is no object to hold the
instance data for the tied variable. The callbacks in the dispatch table
are called not as object methods but as simple subroutines. If there is to
be any instance information for a variable tied using \'Tie::OneOff\' it must
be in lexical variables that are referenced by the callback closures.
\'Tie::OneOff\' does not itself provide any default callbacks. This can make
defining a full featured hash interface rather tedious. To simplify matters
the element \'BASE\' in the dispatch table can be used to specify a \"base
object\" whose methods provide the default callbacks. If a reference to an
unblessed Perl variable is specified as the \'BASE\' then the variable is
blessed into the appropriate \'Tie::StdXXXX\' package. In this case the
unblessed variable used as the base must, of course, be of the same type as
the variable that is being tied.
In \'make_counter()\' in the synopsis above, the variable \'$i\' gets blessed
into \'Tie::StdScalar\'. Since there is no explict STORE in the dispatch
table, an attempt to store into a counter is implemented by calling
\'(\\$i)->STORE(AATT_)\' which in turn is resolved as
\'Tie::StdScalar::STORE(\\$i,AATT_)\' which in turn is equivalent to \'$i=shift\'.
Since many tied variables need only a \'FETCH\' method \'Tie::OneOff\' ties can
also be specified by giving a simple code reference that is taken to be the
variable\'s \'FETCH\' callback.
For convience the class methods \'scalar\', \'hash\' and \'array\' take the same
arguments as the tie inferface and return a reference to an anonymous tied
variable. The class method \'lvalue\' is like \'scalar\' but returns an lvalue
rather than a reference.
|
RPM found in directory: /packages/linux-pbone/ftp5.gwdg.de/pub/opensuse/repositories/devel:/languages:/perl:/CPAN-T/15.5/noarch |
