Contains vs is in
Did someone once say that between "contains" and "is in", one is faster than the other? -- Jacqueline Landman Gay | jac...@hyperactivesw.com HyperActive Software | http://www.hyperactivesw.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
> On Dec 30, 2016, at 2:32 PM, J. Landman Gay wrote: > > Did someone once say that between "contains" and "is in", one is faster than > the other? This is a great question. One of the engineers on the LC team would be needed to answer this one. Best regards, Mark Talluto livecloud.io canelasoftware.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
> Jacqueline L.G. wrote: > > Did someone once say that between "contains" and "is in", one is faster > > than the other? Mark T. wrote: > This is a great question. One of the engineers on the LC team would be > needed to answer this one. There is a real big difference: "is in" are 5 chars and "contains" are 8 chars to type. This means, the second variant needs 60% more time and bytes. Flock makes also muck ;-) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
Mark Talluto wrote:
>> On Dec 30, 2016, at 2:32 PM, J. Landman Gay wrote:
>>
>> Did someone once say that between "contains" and "is in",
>> one is faster than the other?
>
> This is a great question. One of the engineers on the LC team would
> be needed to answer this one.
Or you could test it:
on mouseUp
put 100 into n
put the millisecs into t
repeat n
put ("this is a string with foo in it" contains "foo") into r2
end repeat
put the millisecs - t into t2
put the millisecs into t
repeat n
put ("foo" is in "this is a string with foo in it") into r1
end repeat
put the millisecs - t into t1
put t1 && t2
end mouseUp
--
Richard Gaskin
Fourth World Systems
Software Design and Development for the Desktop, Mobile, and the Web
ambassa...@fourthworld.comhttp://www.FourthWorld.com
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Re: Contains vs is in
[There is always some crazy time overcrossing here, I posted half an hour
before you.]
I have here the following result with your code (in average).
There is a "contains"-repeat and a "is in"-repeat.
If I use one as first and the other as second repeat loop I get that the one
that is called first is a little bit faster ...
Isn't it that deep in the stomach of LC both use the same offset(substring,
string) routine?
Richard G. wrote:
> Or you could test it:
>
> on mouseUp
> put 100 into n
>
> put the millisecs into t
> repeat n
>put ("this is a string with foo in it" contains "foo") into r2
> end repeat
> put the millisecs - t into t2
>
> put the millisecs into t
> repeat n
>put ("foo" is in "this is a string with foo in it") into r1
> end repeat
> put the millisecs - t into t1
>
> put t1 && t2
> end mouseUp
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Re: Contains vs is in
hh wrote: > There is a "contains"-repeat and a "is in"-repeat. > If I use one as first and the other as second repeat loop I get that > the one that is called first is a little bit faster ... > > Isn't it that deep in the stomach of LC both use the same > offset(substring, string) routine? I would imagine so. If not, perhaps they should. I can't think of a case where they would need to produce different results. -- Richard Gaskin Fourth World Systems Software Design and Development for the Desktop, Mobile, and the Web ambassa...@fourthworld.comhttp://www.FourthWorld.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
On 1/2/17 4:44 PM, Richard Gaskin wrote: hh wrote: There is a "contains"-repeat and a "is in"-repeat. If I use one as first and the other as second repeat loop I get that the one that is called first is a little bit faster ... Isn't it that deep in the stomach of LC both use the same offset(substring, string) routine? I would imagine so. If not, perhaps they should. I can't think of a case where they would need to produce different results. They come out the same for me, but I vaguely remember someone said they perform differently. Maybe I'm thinking of something else. -- Jacqueline Landman Gay | jac...@hyperactivesw.com HyperActive Software | http://www.hyperactivesw.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
But there is interestingly the fact that both are faster than
put offset("foo","this is a string with foo in it") > 0 into r3
(seen by 'enlarging' your test).
Quite clear because "is in" and "contains" do the ">0" test in the engine,
while the above needs a further comparison of two numbers:
put offset("foo","this is a string with foo in it") into r3
without checking the function return is fastest.
I wasn't aware of that, good to know, "is in"/"contains" is 10% faster than
"offset() > 0".
[And once again: LC 6 is here 2.5 times faster than LC 9 using your test.]
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Re: Contains vs is in
hh wrote: > I wasn't aware of that, good to know, "is in"/"contains" is 10% > faster than "offset() > 0". But as with many benchmarks, it's helpful to keep the absolute times in mind. In my quickie test script I had to use 1,000,000 iterations just to get any appreciable duration to test. 10% of a fraction is a nanosecond isn't much to lose sleep over. :) -- Richard Gaskin Fourth World Systems Software Design and Development for the Desktop, Mobile, and the Web ambassa...@fourthworld.comhttp://www.FourthWorld.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
says the guy who doesn't scrape. On Mon, Jan 2, 2017 at 6:14 PM, Richard Gaskin wrote: > hh wrote: > > > I wasn't aware of that, good to know, "is in"/"contains" is 10% > > faster than "offset() > 0". > > But as with many benchmarks, it's helpful to keep the absolute times in > mind. > > In my quickie test script I had to use 1,000,000 iterations just to get > any appreciable duration to test. > > 10% of a fraction is a nanosecond isn't much to lose sleep over. :) > > -- > Richard Gaskin > Fourth World Systems > Software Design and Development for the Desktop, Mobile, and the Web > > ambassa...@fourthworld.comhttp://www.FourthWorld.com > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > -- On the first day, God created the heavens and the Earth On the second day, God created the oceans. On the third day, God put the animals on hold for a few hours, and did a little diving. And God said, "This is good." ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
? -- Richard Gaskin Fourth World Systems Mike Kerner wrote: says the guy who doesn't scrape. On Mon, Jan 2, 2017 at 6:14 PM, Richard Gaskin wrote: hh wrote: > I wasn't aware of that, good to know, "is in"/"contains" is 10% > faster than "offset() > 0". But as with many benchmarks, it's helpful to keep the absolute times in mind. In my quickie test script I had to use 1,000,000 iterations just to get any appreciable duration to test. 10% of a fraction is a nanosecond isn't much to lose sleep over. :) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
I think he means 10% of 1/100 of 1,000,000 iterations of a nano-million-dollar are 1 dollar. > Richard Gaskin wrote: > ? >> Mike Kerner wrote: >> > says the guy who doesn't scrape. >> > >> > On Mon, Jan 2, 2017 at 6:14 PM, Richard Gaskin wrote: >> > >> >> hh wrote: >> >> >> >> > I wasn't aware of that, good to know, "is in"/"contains" is 10% >> >> > faster than "offset() > 0". >> >> >> >> But as with many benchmarks, it's helpful to keep the absolute times in >> >> mind. >> >> >> >> In my quickie test script I had to use 1,000,000 iterations just to get >> >> any appreciable duration to test. >> >> >> >> 10% of a fraction is a nanosecond isn't much to lose sleep over. :) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
I mean if you do web scraping and use LC to analyze the results, a million is a small number. On Tue, Jan 3, 2017 at 2:34 PM, hh wrote: > I think he means > > 10% of 1/100 of 1,000,000 iterations of a nano-million-dollar are 1 dollar. > > > Richard Gaskin wrote: > > ? > >> Mike Kerner wrote: > >> > says the guy who doesn't scrape. > >> > > >> > On Mon, Jan 2, 2017 at 6:14 PM, Richard Gaskin wrote: > >> > > >> >> hh wrote: > >> >> > >> >> > I wasn't aware of that, good to know, "is in"/"contains" is 10% > >> >> > faster than "offset() > 0". > >> >> > >> >> But as with many benchmarks, it's helpful to keep the absolute times > in > >> >> mind. > >> >> > >> >> In my quickie test script I had to use 1,000,000 iterations just to > get > >> >> any appreciable duration to test. > >> >> > >> >> 10% of a fraction is a nanosecond isn't much to lose sleep over. :) > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > -- On the first day, God created the heavens and the Earth On the second day, God created the oceans. On the third day, God put the animals on hold for a few hours, and did a little diving. And God said, "This is good." ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
Thanks. I've been accused of over-obsessing about performance so often that it didn't occur to me my comment could be seen as erring the other way. :) I've done scraping, but fortunately here the simplest syntax is also the more efficient. And even in tasks requiring fewer than a million iterations, it's often helpful to adopt habits that favor performance. I like to think of it as the opposite of technical debt, a sort of savings account from which you can later draw clock cycles for new features or more thorough error-checking as needed. But on balance, for all the benchmarking I've done over the years I try to remain mindful of the ROI of such efforts. Sometimes it's quite high and well worth it. Other times, not so much. Some optimizations come at a cost not only to initial development as various options are explored, but also to ongoing maintenance. Sometimes highly-optimized code is really hard to read, and harder to fix or extend. With any quantification, percentages are only part of a complete breakfast. I find it helpful to keep absolute values in mind as well. -- Richard Gaskin Fourth World Systems hh wrote: > I think he means > > 10% of 1/100 of 1,000,000 iterations of a nano-million-dollar are 1 > dollar. > >> Richard Gaskin wrote: >> ? >>> Mike Kerner wrote: >>> > says the guy who doesn't scrape. >>> > >>> > On Mon, Jan 2, 2017 at 6:14 PM, Richard Gaskin wrote: >>> > >>> >> hh wrote: >>> >> >>> >> > I wasn't aware of that, good to know, "is in"/"contains" is 10% >>> >> > faster than "offset() > 0". >>> >> >>> >> But as with many benchmarks, it's helpful to keep the absolute times in >>> >> mind. >>> >> >>> >> In my quickie test script I had to use 1,000,000 iterations just to get >>> >> any appreciable duration to test. >>> >> >>> >> 10% of a fraction is a nanosecond isn't much to lose sleep over. >>> >> :) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
Speaking of which, is it possible to scrape values from web controls like menus and check boxes? Bob S On Jan 3, 2017, at 12:12 , Mike Kerner mailto:mikeker...@roadrunner.com>> wrote: I mean if you do web scraping and use LC to analyze the results, a million is a small number. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
the short answer is "yes", but it can be more complicated as it may require some javascript execution to pull the data from the server. It depends on the site you are scraping. You can also (possibly) use a service that can yank that for you. On Tue, Jan 3, 2017 at 4:05 PM, Bob Sneidar wrote: > Speaking of which, is it possible to scrape values from web controls like > menus and check boxes? > > Bob S > > > On Jan 3, 2017, at 12:12 , Mike Kerner mikeker...@roadrunner.com>> wrote: > > I mean if you do web scraping and use LC to analyze the results, a million > is a small number. > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > -- On the first day, God created the heavens and the Earth On the second day, God created the oceans. On the third day, God put the animals on hold for a few hours, and did a little diving. And God said, "This is good." ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
I interact with copier interfaces quite a lot and the process of backing up the data involves going through various pages and typing what I see there into a text file. I have always thought it would be great to write an app that can do it for me, but I have never been able to scrape anything more than the HTML text displayed on the page. I will have to look into ways to use Javascript to do it. If it requires already knowing what the values are though, I'm afraid I might meet with unsurpassable difficluty. Bob S On Jan 3, 2017, at 15:02 , Mike Kerner mailto:mikeker...@roadrunner.com>> wrote: the short answer is "yes", but it can be more complicated as it may require some javascript execution to pull the data from the server. It depends on the site you are scraping. You can also (possibly) use a service that can yank that for you. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
'contains' and 'is in' are implemented exactly the same in LiveCode Script, so there shouldn't be any difference. However there is an interesting subtlety that emerges when you consider what these two bits of syntax should do, which explains why they are different in LCB. When we say 'A contains B' where A is some sort of sequence (ordered set), then I would argue we really mean that B is a subsequence of A. On the other hand I think the interpretation of 'is in' is the same as that of 'is among the elements of'. Thus 'contains' is actually a relation between sequences and sequences, whereas 'is in' is one between elements and sequences. This makes no difference in LCS for strings because the type of the sequence is the same as the type of the element, namely they are strings. However it does mean that the following two should be considered anomalous: 1) In LCS, 'is in' does not restrict the left hand side to a single char 2) In LCS, no string other than empty 'contains' empty Both of these anomalies are rectified in LCB. The situation becomes clearer when using an LCB list, where contains is a syntax error, and is in is only true if listA occurs as an *element* of listB, rather than a subsequence. Moreover contains [] is always true. tl;dr - there should be no performance difference between 'contains' and 'is in' in LCS. On Tue, Jan 3, 2017 at 11:35 PM Bob Sneidar wrote: > I interact with copier interfaces quite a lot and the process of backing > up the data involves going through various pages and typing what I see > there into a text file. I have always thought it would be great to write an > app that can do it for me, but I have never been able to scrape anything > more than the HTML text displayed on the page. > > I will have to look into ways to use Javascript to do it. If it requires > already knowing what the values are though, I'm afraid I might meet with > unsurpassable difficluty. > > Bob S > > > On Jan 3, 2017, at 15:02 , Mike Kerner mikeker...@roadrunner.com>> wrote: > > the short answer is "yes", but it can be more complicated as it may require > some javascript execution to pull the data from the server. It depends on > the site you are scraping. You can also (possibly) use a service that can > yank that for you. > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
Peter has pointed out that I am technically using the word 'subsequence' in error, and should probably have used 'substring' instead! (cf https://en.wikipedia.org/wiki/Subsequence vs https://en.wikipedia.org/wiki/Substring) On Wed, Jan 4, 2017 at 10:16 AM Ali Lloyd wrote: > 'contains' and 'is in' are implemented exactly the same in LiveCode > Script, so there shouldn't be any difference. However there is an > interesting subtlety that emerges when you consider what these two bits of > syntax should do, which explains why they are different in LCB. > > When we say 'A contains B' where A is some sort of sequence (ordered set), > then I would argue we really mean that B is a subsequence of A. On the > other hand I think the interpretation of 'is in' is the same as that of 'is > among the elements of'. > > Thus 'contains' is actually a relation between sequences and sequences, > whereas 'is in' is one between elements and sequences. This makes no > difference in LCS for strings because the type of the sequence is the same > as the type of the element, namely they are strings. However it does mean > that the following two should be considered anomalous: > > 1) In LCS, 'is in' does not restrict the left hand side to a single char > 2) In LCS, no string other than empty 'contains' empty > > Both of these anomalies are rectified in LCB. The situation becomes > clearer when using an LCB list, where contains is a syntax > error, and is in is only true if listA occurs as an > *element* of listB, rather than a subsequence. Moreover contains [] > is always true. > > > tl;dr - there should be no performance difference between 'contains' and > 'is in' in LCS. > > > On Tue, Jan 3, 2017 at 11:35 PM Bob Sneidar > wrote: > > I interact with copier interfaces quite a lot and the process of backing > up the data involves going through various pages and typing what I see > there into a text file. I have always thought it would be great to write an > app that can do it for me, but I have never been able to scrape anything > more than the HTML text displayed on the page. > > I will have to look into ways to use Javascript to do it. If it requires > already knowing what the values are though, I'm afraid I might meet with > unsurpassable difficluty. > > Bob S > > > On Jan 3, 2017, at 15:02 , Mike Kerner mikeker...@roadrunner.com>> wrote: > > the short answer is "yes", but it can be more complicated as it may require > some javascript execution to pull the data from the server. It depends on > the site you are scraping. You can also (possibly) use a service that can > yank that for you. > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
WHAT? There is some subtlety that I am missing, Ali. On Wed, Jan 4, 2017 at 5:22 AM, Ali Lloyd wrote: > Peter has pointed out that I am technically using the word 'subsequence' in > error, and should probably have used 'substring' instead! > (cf https://en.wikipedia.org/wiki/Subsequence vs > https://en.wikipedia.org/wiki/Substring) > > On Wed, Jan 4, 2017 at 10:16 AM Ali Lloyd wrote: > > > 'contains' and 'is in' are implemented exactly the same in LiveCode > > Script, so there shouldn't be any difference. However there is an > > interesting subtlety that emerges when you consider what these two bits > of > > syntax should do, which explains why they are different in LCB. > > > > When we say 'A contains B' where A is some sort of sequence (ordered > set), > > then I would argue we really mean that B is a subsequence of A. On the > > other hand I think the interpretation of 'is in' is the same as that of > 'is > > among the elements of'. > > > > Thus 'contains' is actually a relation between sequences and sequences, > > whereas 'is in' is one between elements and sequences. This makes no > > difference in LCS for strings because the type of the sequence is the > same > > as the type of the element, namely they are strings. However it does mean > > that the following two should be considered anomalous: > > > > 1) In LCS, 'is in' does not restrict the left hand side to a single char > > 2) In LCS, no string other than empty 'contains' empty > > > > Both of these anomalies are rectified in LCB. The situation becomes > > clearer when using an LCB list, where contains is a > syntax > > error, and is in is only true if listA occurs as an > > *element* of listB, rather than a subsequence. Moreover contains > [] > > is always true. > > > > > > tl;dr - there should be no performance difference between 'contains' and > > 'is in' in LCS. > > > > > > On Tue, Jan 3, 2017 at 11:35 PM Bob Sneidar > > > wrote: > > > > I interact with copier interfaces quite a lot and the process of backing > > up the data involves going through various pages and typing what I see > > there into a text file. I have always thought it would be great to write > an > > app that can do it for me, but I have never been able to scrape anything > > more than the HTML text displayed on the page. > > > > I will have to look into ways to use Javascript to do it. If it requires > > already knowing what the values are though, I'm afraid I might meet with > > unsurpassable difficluty. > > > > Bob S > > > > > > On Jan 3, 2017, at 15:02 , Mike Kerner mailto: > > mikeker...@roadrunner.com>> wrote: > > > > the short answer is "yes", but it can be more complicated as it may > require > > some javascript execution to pull the data from the server. It depends > on > > the site you are scraping. You can also (possibly) use a service that > can > > yank that for you. > > > > ___ > > use-livecode mailing list > > use-livecode@lists.runrev.com > > Please visit this url to subscribe, unsubscribe and manage your > > subscription preferences: > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > -- On the first day, God created the heavens and the Earth On the second day, God created the oceans. On the third day, God put the animals on hold for a few hours, and did a little diving. And God said, "This is good." ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
As an example, consider a list ["a", "b", "c"]. "a" is in the list. But the list ["a", "b"] is *not* in the list, as it is not an element of the list - all the elements of the list are strings, and ["a", "b"] is a list. However, ["a", "b", "c"] *does* contain ["a", "b"] as the latter occurs as a 'substring' (in the sense of the wikipedia links I posted). On Wed, Jan 4, 2017 at 1:39 PM Mike Kerner wrote: > WHAT? > There is some subtlety that I am missing, Ali. > > On Wed, Jan 4, 2017 at 5:22 AM, Ali Lloyd wrote: > > > Peter has pointed out that I am technically using the word 'subsequence' > in > > error, and should probably have used 'substring' instead! > > (cf https://en.wikipedia.org/wiki/Subsequence vs > > https://en.wikipedia.org/wiki/Substring) > > > > On Wed, Jan 4, 2017 at 10:16 AM Ali Lloyd > wrote: > > > > > 'contains' and 'is in' are implemented exactly the same in LiveCode > > > Script, so there shouldn't be any difference. However there is an > > > interesting subtlety that emerges when you consider what these two bits > > of > > > syntax should do, which explains why they are different in LCB. > > > > > > When we say 'A contains B' where A is some sort of sequence (ordered > > set), > > > then I would argue we really mean that B is a subsequence of A. On the > > > other hand I think the interpretation of 'is in' is the same as that of > > 'is > > > among the elements of'. > > > > > > Thus 'contains' is actually a relation between sequences and sequences, > > > whereas 'is in' is one between elements and sequences. This makes no > > > difference in LCS for strings because the type of the sequence is the > > same > > > as the type of the element, namely they are strings. However it does > mean > > > that the following two should be considered anomalous: > > > > > > 1) In LCS, 'is in' does not restrict the left hand side to a single > char > > > 2) In LCS, no string other than empty 'contains' empty > > > > > > Both of these anomalies are rectified in LCB. The situation becomes > > > clearer when using an LCB list, where contains is a > > syntax > > > error, and is in is only true if listA occurs as an > > > *element* of listB, rather than a subsequence. Moreover contains > > [] > > > is always true. > > > > > > > > > tl;dr - there should be no performance difference between 'contains' > and > > > 'is in' in LCS. > > > > > > > > > On Tue, Jan 3, 2017 at 11:35 PM Bob Sneidar < > bobsnei...@iotecdigital.com > > > > > > wrote: > > > > > > I interact with copier interfaces quite a lot and the process of > backing > > > up the data involves going through various pages and typing what I see > > > there into a text file. I have always thought it would be great to > write > > an > > > app that can do it for me, but I have never been able to scrape > anything > > > more than the HTML text displayed on the page. > > > > > > I will have to look into ways to use Javascript to do it. If it > requires > > > already knowing what the values are though, I'm afraid I might meet > with > > > unsurpassable difficluty. > > > > > > Bob S > > > > > > > > > On Jan 3, 2017, at 15:02 , Mike Kerner > mailto: > > > mikeker...@roadrunner.com>> wrote: > > > > > > the short answer is "yes", but it can be more complicated as it may > > require > > > some javascript execution to pull the data from the server. It depends > > on > > > the site you are scraping. You can also (possibly) use a service that > > can > > > yank that for you. > > > > > > ___ > > > use-livecode mailing list > > > use-livecode@lists.runrev.com > > > Please visit this url to subscribe, unsubscribe and manage your > > > subscription preferences: > > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > > > > > > ___ > > use-livecode mailing list > > use-livecode@lists.runrev.com > > Please visit this url to subscribe, unsubscribe and manage your > > subscription preferences: > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > > > > -- > On the first day, God created the heavens and the Earth > On the second day, God created the oceans. > On the third day, God put the animals on hold for a few hours, >and did a little diving. > And God said, "This is good." > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
(LC Builder 'contains' vs 'is in') = TMHO this abstract writing of Ali's examples is easy to remember, the different "level" of the comparison is visible by the brackets. x "is in" A if and only if A "contains" [x]. (x "is in" A and y "is in" A) if and only if A contains [x,y]. etc. where A is a list, x,y is any. >> Definitions. Let A and B be lists. >> x "is in" A if and only if x is an element of A. >> B "contains" A if and only if every element of A "is in" B. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
(LC Builder 'contains' vs 'is in') = Ali, are the following TRUE statements? 1. Every list "contains" the empty list. 2. [x] "contains" [x, x]. 3. nothing "is in" the empty list. > (Corrected in line 5 contains to "contains"): > TMHO this abstract writing of Ali's examples is easy to remember, > the different "level" of the comparison is visible by the brackets. > > x "is in" A if and only if A "contains" [x]. > (x "is in" A and y "is in" A) if and only if A "contains" [x,y]. > etc. > where A is a list, x,y is any. > > > >> Definitions. Let A and B be lists. > >> x "is in" A if and only if x is an element of A. > >> B "contains" A if and only if every element of A "is in" B. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Contains vs is in
Please forget my last two posts, they contain wrong statements. Haven't seen that this is already implemented using the term "subsequence of elements": >From the dictionary. Target contains Needle if and only if the elements of Needle occur as a _subsequence of the elements_ of Target. So I should use the dictionary and can test by myself. I thought erroneously of analogies to (counted) sets, sorry. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
