arrays-of-scalars
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=head1 TITLE
Standard support for opening i/o handles on scalars and
arrays-of-scalars
=head1 VERSION
Maintainer: Eryq (Erik Dorfman) <[EMAIL PROTECTED]>
Date: 23 Aug 2000
Mailing List: [EMAIL PROTECTED]
Version: 1
Number: 186
Status: Developing
=head1 ABSTRACT
It's extremely useful to be able to open an i/o handle on
common in-core data structures, such as scalars or arrays-of-lines.
The CPAN modules IO::Scalar, IO::ScalarArray, and IO::Lines
currently provide some of this functionality, but their pure-Perl
implementation (chosen for portability) is not as fast or
memory-efficient
as a native implementation could be. Additionally, since they are not
part of the standard Perl distribution, many developers are either
unaware of their existence or unwilling to obtain and install them.
This RFC proposes that support for "in-core i/o" be folded
into the Perl distribution as a standard extension module, making
use of native C code for speed.
=head1 DESCRIPTION
=head1 IMPLEMENTATION
As described in the ABSTRACT above.
The following I/O handle classes are proposed as minimally necessary;
they are taken from existing Perl5 CPAN modules with the same names:
=over 4
=item IO::Scalar
An I/O handle which can be opened on a scalar (string) variable.
We simply treat the bytes of the scalar as a "virtual file".
=item IO::ScalarArray
An I/O handle which can be opened on an array of scalar (string)
variables. Here, the "virtual file" is defined as the concatenation
of the scalars in the array. One very common way to obtain such a
data structure is to slurp a file into an array.
=back
If Perl6 follows Java's example of distinguishing "bytes" from
"characters", then it should be understood that the proposed I/O handles
manipulate I<bytes>, not characters. That is, the Java equivalents
are classes like C<java.io.ByteArrayInputStream>.
Character-based I/O should be handled by some additional conversion
mechanism which is wrapped around byte-based I/O; this mechanism
should be applicable to I<any> I/O stream. A look at the Java
implementation of byte-oriented "input/output streams" versus
character-oriented "readers and writers" is worthwhile for this.
=head1 REFERENCES
IO::Scalar (CPAN)
IO::ScalarArray (CPAN)
