use IO::ScalarArray; @data = ("My mes", "sage:\n"); ### Open a handle on an array, and append to it: $AH = new IO::ScalarArray \@data; $AH->print("Hello"); $AH->print(", world!\nBye now!\n"); print "The array is now: ", @data, "\n"; ### Open a handle on an array, read it line-by-line, then close it: $AH = new IO::ScalarArray \@data; while (defined($_ = $AH->getline)) { print "Got line: $_"; } $AH->close; ### Open a handle on an array, and slurp in all the lines: $AH = new IO::ScalarArray \@data; print "All lines:\n", $AH->getlines; ### Get the current position (either of two ways): $pos = $AH->getpos; $offset = $AH->tell; ### Set the current position (either of two ways): $AH->setpos($pos); $AH->seek($offset, 0); ### Open an anonymous temporary array: $AH = new IO::ScalarArray; $AH->print("Hi there!"); print "I printed: ", @{$AH->aref}, "\n"; ### get at value
Don't like OO for your I/O? No problem. Thanks to the magic of an invisible tie(), the following now works out of the box, just as it does with IO::Handle:
use IO::ScalarArray; @data = ("My mes", "sage:\n"); ### Open a handle on an array, and append to it: $AH = new IO::ScalarArray \@data; print $AH "Hello"; print $AH ", world!\nBye now!\n"; print "The array is now: ", @data, "\n"; ### Open a handle on a string, read it line-by-line, then close it: $AH = new IO::ScalarArray \@data; while (<$AH>) { print "Got line: $_"; } close $AH; ### Open a handle on a string, and slurp in all the lines: $AH = new IO::ScalarArray \@data; print "All lines:\n", <$AH>; ### Get the current position (WARNING: requires 5.6): $offset = tell $AH; ### Set the current position (WARNING: requires 5.6): seek $AH, $offset, 0; ### Open an anonymous temporary scalar: $AH = new IO::ScalarArray; print $AH "Hi there!"; print "I printed: ", @{$AH->aref}, "\n"; ### get at value
And for you folks with 1.x code out there: the old tie() style still works, though this is unnecessary and deprecated:
use IO::ScalarArray; ### Writing to a scalar... my @a; tie *OUT, 'IO::ScalarArray', \@a; print OUT "line 1\nline 2\n", "line 3\n"; print "Array is now: ", @a, "\n" ### Reading and writing an anonymous scalar... tie *OUT, 'IO::ScalarArray'; print OUT "line 1\nline 2\n", "line 3\n"; tied(OUT)->seek(0,0); while (<OUT>) { print "Got line: ", $_; }
The IO::ScalarArray class implements objects which behave just like IO::Handle (or FileHandle) objects, except that you may use them to write to (or read from) arrays of scalars. Logically, an array of scalars defines an in-core ``file'' whose contents are the concatenation of the scalars in the array. The handles created by this class are automatically "tiehandle"d (though please see ``WARNINGS'' for information relevant to your Perl version).
For writing large amounts of data with individual print() statements, this class is likely to be more efficient than IO::Scalar.
Basically, this:
my @a; $AH = new IO::ScalarArray \@a; $AH->print("Hel", "lo, "); ### OO style $AH->print("world!\n"); ### ditto
Or this:
my @a; $AH = new IO::ScalarArray \@a; print $AH "Hel", "lo, "; ### non-OO style print $AH "world!\n"; ### ditto
Causes @a to be set to the following array of 3 strings:
( "Hel" , "lo, " , "world!\n" )
See IO::Scalar and compare with this class.
Returns the self object on success, undefined on error.
Currently, this always causes a ``seek to the end of the array'' and generates a new array entry. This may change in the future.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.