How to test a variable against another variable?

[whenever]

I am trying to write a filter which will add links to Google cache results to allow continuing using the cache, just like this userscript does.

I intend to add links only for those urls which are from the same host, so I use below code to extract the host address and sotre it in a global variable for later use.

Code:

(This is Google's cache of <a[^>]+>http://\1/*</a>)\0$SET(currentHost=\1)

The next step is to match only the urls from the same host. I tried below code but it seems the $GET command can't be expanded in match field just like the help file stated:

Code:

<a*href=$AV($GET(currentHost)/\2)*</a>

Then I tried to capture the host part into a variable:

Code:

<a*href=$AV(\7/\2)*</a>

and tested it with the currentHost variable in the replace field but it doesn't work either.

Code:

$TST(\7=$GET(currentHost))$SET(......)

Any ideas?

[Kye-U]

I find variables confusing sometimes; try reading Sidki's "Techniques" file, I think some of it might apply to what you're trying to accomplish: http://sidki.proxfilter.net/prox/sidki-e...niques.txt

[whenever]

I read that already and even searched sidki's config set but couldn't find an example on testing variable against variable.

Is there any other way to do what I want to do?

[whenever]

(Aug. 21, 2008 04:04 AM)whenever Wrote:  The next step is to match only the urls from the same host. I tried below code but it seems the $GET command can't be expanded in match field just like the help file stated:

Code:

<a*href=$AV($GET(currentHost)/\2)*</a>

Finally worked out a way by using a memory block list for the hostname match.

The below filter is just for demonstrating the technique and may not ready for real use.

Code:

[Patterns]
Name = "Add cache links to Google cache results page"
Active = TRUE
URL = "[^/]+/search\?*q=cache"
Limit = 256
Match = "(This is Google*s cache of <a[^>]+>http://\1/*</a>)\0$SET(currentHost=\1)$ADDLST(Mem-Temp,\1)|"
        "(<a*href=$AV(http://$LST(Mem-Temp)/\1|/\1)*</a>)\0$SET(2= <a href="http://www.google.com/search?hl=en&q=cache:http://$GET(currentHost)/\1"><img src="http://www.google.com/favicon.ico" style="border: none;" /></a>)"
Replace = "\0\2"

[z12]

whenever Wrote:The next step is to match only the urls from the same host. I tried below code but it seems the $GET command can't be expanded in match field just like the help file stated:

Code:

<a*href=$AV($GET(currentHost)/\2)*</a>

...snip...
Any ideas?

Here's a test filter that does what you want, I think.

Code:

[Patterns]
Name = "New HTML filter"
Active = FALSE
Limit = 256
Match = "$SET(foo=http://www.foobar.com)"
        "(<a*href=$AV($TST(foo)/\2)*</a>)\3"
Replace = "\3"

In the log window, these will match:

Code:

<a href="http://www.foobar.com/foo_for_all/" >foo for all </a>
<a href="http://www.foobar.com/foo_for_one/" >foo for one </a>

This one does not:

Code:

<a href="http://www.nofoo.com/foo_for_all/" >foo for all </a>

HTH
z12

[whenever]

Thank you z12. I found that trick was documented in the help file too, just inside the $TST() command section.

Each time I reread the help file, I learn something which was not noticed or understood before.

So, here is an improved filter without using a memory block file.

Code:

[Patterns]
Name = "Add cache links to Google cache results page"
Active = TRUE
URL = "$TYPE(htm)[^/]+/search\?*q=cache"
Limit = 256
Match = "This is Google*s cache of <a[^>]+>http://\1/*</a>$SET(currentHost=\1)PrxFail|"
        "(<a*</a>&&*href=$AV(http://$TST(currentHost)/\1|/\1)*)\0$SET(2= <a href="http://www.google.com/search?hl=en&q=cache:http://$GET(currentHost)/\1"><img src="http://www.google.com/favicon.ico" style="border: none;" /></a>)"
Replace = "\0\2"

[z12]

whenever Wrote:Each time I reread the help file, I learn something which was not noticed or understood before.

Same with me. It's definitely not a file you read just once.

As Kye-U mentioned, sidki's Techniques.txt is also quite helpful.
Especially in regards to variables.

BTW, as per your thread title, this tests if two variables, to & tc, are equal:

Code:

$TST(to=$TST(tc))

While this may seem obvious to some, it took me a while to figure it out.

z12

[whenever]

Great! Now it seems obvious with knowing the above trick.

I learned another trick about $TST() at Castlecops, maybe you are interested in it too.

[lnminente]

If you use "This is Google's cache of", this will only work for english people. In my case, being spanish, i see "Esta es la versión en caché de" so it will never match. Please let's tray doing global filters.

How? Taking "currentHost" from the actual url of the cache

Code:

$URL(*cache:*:(*)\5/*)$SET(currentHost=\5)

Code:

[Patterns]
Name = "Google cache: Add cache links to Google cache results page {whenever,ln}081010"
Active = TRUE
URL = "$TYPE(htm)[^/]+/search\?*q=cache"
Bounds = "$NEST(<a\s,</a>)"
Limit = 256
Match = "(*href="
        "$TST(V_Postbody=1)$URL((*cache:*:)\4(*)\5/*)$SET(currentHost=\5)"
        "$AV(http://$TST(currentHost)/\1|/\1)*)\2"
Replace = "\2<a href="http://www.google.com/search?q=cache:http://$GET(currentHost)/\1"><img src="http://www.google.com/favicon.ico" style="border: none;" /></a>"

I like this filter, thanks for it

Updated: Changed "/search?hl=en&q=cache" to "/search?q=cache"

[whenever]

That's better. I made some improvements based on your filter to cover the below situation:

cache:www.test.com&other=
No http:// between, no ended "/"

cache:www.test.com
currentHost is the last parameter

Code:

[Patterns]
Name = "Add cache links to Google cache results page {whenever,ln}081010"
Active = TRUE
URL = "$TYPE(htm)[^/]+/search\?*q=cache"
Bounds = "<a*</a>"
Limit = 256
Match = "$URL(*cache:(http://|)(\3)([/&]*|))$SET(currentHost=\3)"
        "(*href=$AV(http://$TST(currentHost)/\1|/\1)*)\2"
Replace = "\2<a href="http://www.google.com/search?hl=en&q=cache:http://$GET(currentHost)/\1"><img src="http://www.google.com/favicon.ico" style="border: none;" /></a>"

[lnminente]

Better again. Thanks!

[whenever]

Since host extraction is excuted each time, there is no need to use a global var any longer. The below new version also improved the host extraction and took care of the :// encoding.

Code:

[Patterns]
Name = "Add cache links to Google cache results page {whenever,ln}081011"
Active = TRUE
URL = "$TYPE(htm)[^/]+/search\?*q=cache"
Bounds = "<a*</a>"
Limit = 256
Match = "$URL(*cache(:|%3a)(http(://|%3a%2f%2f)|)([^/&]+)\1*)"
        "(*href=$AV(http://$TST(\1)/\2|/\2)*)\3"
Replace = "\3<a href="http://www.google.com/search?q=cache:http://\1/\2"><img src="http://www.google.com/favicon.ico" style="border: none;" /></a>"

[z12]

whenever Wrote:I learned another trick about $TST() at Castlecops, maybe you are interested in it too.

At first glance, the castlecops $TST looks a bit odd.

Basically it's just this:

Code:

$TST(VariableName=Matching expression)
$TST(VariableName=*)
...
$TST(keyword=*)
$TST(keyword=\1)

Both the * and \1 match the current value of the VariableName.
The \1 has the added bonus of saving that value.
You can do this wherever you can use $TST().

BTW, personally, I would put the \s back into your filters Bounds expression.

Code:

Bounds = "<a\s*</a>"

It's a bit safer.

Perhaps you should post your filter in Website Customization when your done with it.
More people will probably see it there.

z12

[whenever]

You are right on the \s. The fixed version is posted here.

[lnminente]

Agree!!

I used sometimes a\s but sometimes i removed it to test for area, but i still haven't tested it by now. I will play with (a|area)\s

More ideas are welcome;)

Edited: Deleted what i said about $NEST or $INEST, it's usefull for tables, but not here. It's also confusing sometimes, so i removed it from here for that reason.