Perl script to list matplotlib examples ordered by last commit

findoldexamples.pl

#!/usr/bin/perl

# I don't claim credit for because I haven't written Perl before and just Frankensteined
# it together from these three sites:
# http://stackoverflow.com/a/17727887
# http://www.perlmonks.org/?node_id=97574
# http://perl.about.com/od/filesystem/qt/perl_file_exist.htm

# Note that the script should be placed inside the examples folder of the matplotlib repo.

# Ask git for a list of access times and files
my @logbook = `git whatchanged --pretty=%ai . `;

my %seen;
my $timestamp;
my $filename;

my $date;
my $relpath;

foreach (@logbook) {
    next if /^$/; # skip empty lines
    if (/^:/) {
        next unless /.py$/;          # skip files without .py extension
        chomp ($filename = (split /\t/)[1]);
        $relpath = substr($filename, 9); # because we're in examples/, drop that part from the path when testing existence
        next unless (-e $relpath);   # skip files no longer existing
        $date = substr($timestamp, 0, 10);
        next if ($date eq '2016-04-26');
        next if $seen{$filename};    # skip files already displayed with a newer commit
        print "$timestamp $filename\n";
        $seen{$filename} = 1;
    } else {
        chomp ($timestamp = $_);
    }
}

See the results here (for the present state of matplotlib): https://gist.github.com/discardthree/2d1316c000d45946bdb4df12d8672070