use strict;
use warnings;

my $element = pop; # 'something';

my @attributes;

my %eq = (
    script   => ['defer'],
    label    => ['for'],
    area     => ['nohref'],
    head     => ['profile'],
    option   => ['selected'],
    param    => ['valuetype'],
    table    => ['border','cellpadding','cellspacing','frame','rules',
+'summary'],
    object   => ['archive','classid','codebase','codetype','data','dec
+lare','standby'],
    select   => ['multiple'],
    input    => ['checked','maxlength'],
    frame    => ['noresize'],
    a        => [qw(onblur onfocus )],
    label    => [qw(onblur onfocus )],
    area     => [qw(onblur onfocus )],
    button   => [qw(onblur onfocus )],
    select   => [qw(onblur onfocus onchange multiple size             
+                        )],
    input    => [qw(onblur onfocus onchange          size onselect rea
+donly checked maxlength )],
    textarea => [qw(onblur onfocus onchange               onselect rea
+donly                   )],
    iframe   => ['frameborder','longdesc','marginheight','marginwidth'
+,'scrolling'],
    frame    => ['frameborder','longdesc','marginheight','marginwidth'
+,'scrolling','noresize'],
);

my %matches = (
    '(?:meta)'                                           => ['content'
+,'http-equiv','scheme'],
    '^(?:body|frameset)$'                                => ['onload',
+'onunload'],
    '^(?:a|area)$'                                       => ['coords',
+'shape'],
    '^(?:a|link)$'                                       => ['hreflang
+','rel','rev'],
    '(?:a|area|base|link)'                               => ['href'],
    '(?:a|area|base|link|form)'                          => ['target']
+,
    '(?:a|area|button|input|label|legend|textarea)'      => ['accesske
+y'],
    '(?:a|area|button|input|object|select|textarea)'     => ['tabindex
+'],
    '(?:a|link|script)'                                  => ['charset'
+],
    '(?:a|link|button|input|object|param|script|style)'  => ['type'],
    '^(?:del|ins)$'                                      => ['cite','d
+atetime'],
    '^(?:col|colgroup|tbody|td|tfoot|th|thead|tr)$'      => ['align','
+char','charoff','valign'],
    '^(?:td|th)$'                                        => ['abbr','a
+xis','colspan','headers','rowspan','scope'],
    '(?:col|colgroup)'                                   => ['span'],
    '^(?:input|select)$'                                 => ['size'],
    '^(?:form|input)$'                                   => ['accept']
+,
    '^(?:image|area|input)$'                             => ['alt'],
    '^(?:button|input|optgroup|option|select|textarea)$' => ['disabled
+'],
    '^(?:iframe|img|object)$'                            => ['height']
+,
    '^(?:img|input)$'                                    => ['ismap'],
    '^(?:option|optgroup:)$'                             => ['label'],
    '^(?:style|link|form)$'                              => ['media'],
    '^(?:a|button|form|frame|iframe|img|input|object|map|param|meta|se
+lect|textarea)$' => ['name'],
    '^(?:input|frame|iframe|img|script)$'                => ['src'],
    '^(?:img|input|object)$'                             => ['usemap']
+,
    '^(?:input|option|param|button|li)$'                 => ['value'],
    '^(?:iframe|img|object|table|col|colgroup)$'         => ['width'],
);

my %non_matches = (
    '^(?:base|basefont|head|html|meta|param|script|title|style)$'     
+     => ['class','style'],
    '^(?:applet|base|basefont|bdo|br|frame|iframe|frameset|param|scrip
+t)$' => ['dir'],
    '^(?:base|head|html|meta|script|style|title)$'                    
+     => ['id'],
    '^(?:applet|base|basefont|br|frame|frameset|iframe|param|script)$'
+     => ['lang'],
    '^(?:base|basefont|head|html|meta|param|script|title)$'           
+     => ['title'],
    '^(?:applet|base|basefont|bdo|br|font|frame|frameset|head|html|ifr
+ame|isindex|meta|param|script|style|title)$'
        => ['onclick','ondblclick','onkeydown','onkeypress','onkeyup',
+'onmousedown',
            'onmousemove','onmouseout','onmouseover','onmouseup'
           ],
);

push @attributes, @{$eq{$element}} if exists $eq{$element};
$element =~ qr{$_} and push @attributes, @{$matches{$_}} for keys %mat
+ches;
$element !~ qr{$_} and push @attributes, @{$non_matches{$_}} for keys 
+%non_matches;

print join("\n",sort @attributes);

[download]

foo.pl

#!/usr/bin/perl
use strict;
my $pat = shift;
my $p;
{
  my (%s, %i);
  my $d = my $c = 1; # our regexp will be inside parens, so first back
+ref is 2
  $p = join (
    "",
    map {
      if($s{$_}++){
        "\\".$i{$_}
      }
      else{
        $i{$_}=++$c;
        $c>$d+1 ? '(?!'.join('|',map{"\\".abs}-$c+1..-$d-1).")(\\w)" :
+ "(\\w)";
      }
    } split//,$pat
  );
}
print '(',$p,")\n";


open my $fh, '<', shift;
my %s;
while (<$fh>) {
    my @l = ();
    while (/\b($p)\b/g) {
      push @l, $1 unless $s{$1}++;
    }
    print join (", ",@l), $/ if @l;
}
[download]

try: perl foo.pl fusselkerl /usr/share/dict/words