man VCS::Lite::Delta () - VCS::Lite differences
NAME
VCS::Lite::Delta - VCS::Lite differences
SYNOPSIS
use VCS::Lite;
# diff
my $lit = VCS::Lite->new('/home/me/foo1.txt');
my $lit2 = VCS::Lite->new('/home/me/foo2.txt');
my $difftxt = $lit->delta($lit2)->diff;
print OUTFILE $difftxt;
# patch
my $delt = VCS::Lite::Delta->new('/home/me/patch.diff');
my $lit3 = $lit->patch($delt);
print OUTFILE $lit3->text;
DESCRIPTION
This module provides a Delta class for the differencing functionality of VCS::Lite
new
The underlying object of VCS::Lite::Delta is an array of difference chunks (hunks) such as that returned by Algorithm::Diff.
The constructor takes the following forms:
my $delt = VCS::Lite::Delta->new( '/my/file.diff',$sep); # File name my $delt = VCS::Lite::Delta->new( \*FILE,$sep); # File handle my $delt = VCS::Lite::Delta->new( \$string,$sep); # String as scalar ref my $delt = VCS::Lite::Delta->new( \@foo, $id1, $id2) # Array ref
$sep here is a regexp by which to split strings into tokens. The default is to use the natural perl mechanism of $/ (which is emulated when not reading from a file). The arrayref form is assuming an array of hunks such as the output from Algorithm::Diff::diff.
The other forms assume the input is the text form of a diff listing, either in diff format, or in unified format. The input is parsed, and errors are reported.
diff
print OUTFILE $delt->diff
This generates a standard diff format, for example:
4c4 < Now wherefore stopp'st thou me? --- > Now wherefore stoppest thou me?
udiff
print OUTFILE $delt->udiff
This generates a unified diff (like diff -u) similar to the form in which patches are submitted.
id
my ($id1,$id2) = $delt->id;
$delt2->id('foo.pl@@1','foo.pl@@3')
The id method allows get and set of the names associated with the two elements being diffed. The id is set for delta objects returned by VCS::Lite->diff, to the element IDs of the VCS::Lite objects being diffed.
Diff format omits the file names, hence the IDs will not be populated by new. This is not the case with diff -u format, which includes the file names which are passed in and available as IDs.
hunks
my @hunklist = $delt->hunks
A hunk is a technical term for a section of input containing a difference. Each hunk is an arrayref, containing the block of lines. Each line is itself an arrayref, for example:
[
[ '+', 9, 'use Acme::Foo;'],
[ '-', 9, 'use Acme::Bar;'],
]
See the documentation on Algorithm::Diff for more details of this structure.
COPYRIGHT
Copyright (c) Ivor Williams, 2003-2005
LICENCE
You may use, modify and distribute this module under the same terms as Perl itself.
SEE ALSO
Algorithm::Diff.