Asp Forum - Problem with a regular expression

charles.nadeau

10/13/2006 5:51:00 PM

I have the following code snippet:

require 'net/http'
begin
hdoc =
Net::HTTP.get(URI.parse('http://finance.yahoo.com/lookup?s=Dupont&t=S&...))

re = /<TD>(.*)</TD>/
if hdoc =~ re
print "#{$&}\n"
else
print "Nothing\n"
end
end

The regular expression is never matched when I use the code as shown
above (the expression for re is just a simple one for my testing).
However, if I replace the variable name hdoc by a string like
"<TD>Test</TD>Test1", the regular expression is matched. The type of
hdoc is String. What is wrong with the snippet above. I even tried to
replace hdoc by hdoc.to_s and it still doesn't work.
Thanks for your help!

Charles
------
http://radio.weblogs.co...
http://charlesnadeau.blo...

4 Answers

Aaron Patterson

10/13/2006 6:19:00 PM

Hi,

On Sat, Oct 14, 2006 at 02:55:10AM +0900, charles.nadeau@gmail.com wrote:
> I have the following code snippet:
>
> require 'net/http'
> begin
> hdoc =
> Net::HTTP.get(URI.parse('http://finance.yahoo.com/lookup?s=Dupont&t=S&...))
>
> re = /<TD>(.*)</TD>/
> if hdoc =~ re
> print "#{$&}\n"
> else
> print "Nothing\n"
> end
> end
>
> The regular expression is never matched when I use the code as shown
> above (the expression for re is just a simple one for my testing).
> However, if I replace the variable name hdoc by a string like
> "<TD>Test</TD>Test1", the regular expression is matched. The type of
> hdoc is String. What is wrong with the snippet above. I even tried to
> replace hdoc by hdoc.to_s and it still doesn't work.
> Thanks for your help!

It looks like there are no upper case "TD" tags in the page that you are
fetching. Try this instead:

begin
hdoc = Net::HTTP.get(URI.parse('http://finance.yahoo.com/lookup?s=Dupont&t=S&...))

re = /<TD>(.*)<\/TD>/i
if hdoc =~ re
print "#{$&}\n"
else
print "Nothing\n"
end
end

Your regular expression was case sensitive, I changed it to be case
insensitive by adding the "i" switch.

>
> Charles
> ------
> http://radio.weblogs.co...
> http://charlesnadeau.blo...
>
>

--
Aaron Patterson
http://tenderlovem...

Morton Goldberg

10/13/2006 6:29:00 PM

On Oct 13, 2006, at 1:55 PM, charles.nadeau@gmail.com wrote:

> require 'net/http'
> begin
> hdoc =
> Net::HTTP.get(URI.parse('http://finance.yahoo.c...
> s=Dupont&t=S&m=US'))
>
> re = /<TD>(.*)</TD>/
> if hdoc =~ re
> print "#{$&}\n"
> else
> print "Nothing\n"
> end
> end

Whrn I substitute '\/TD' for '/TD' and make the regex case
insensitive, I get a match. See below:

<code>
! /usr/bin/env ruby -w
require 'net/http'
hdoc = Net::HTTP.get(URI.parse('http://finance.yahoo.c...
s=Dupont&t=S&m=US'))
re = /<TD>(.*)<\/TD>/i ### note changes
if hdoc =~ re
puts "#{$&}\n"
else
puts "Nothing\n"
end
</code>

<result>
<td><table border="0" cellpadding="6" width="100%"
cellspacing="0"><tr><td bgcolor="#556f93"><big><b
style="color:#ffffff">Symbol Lookup </b></big></td></tr></table></
td></tr><tr><td></td></tr></table></td></tr><tr><td><table
cellpadding="0" border="0" cellspacing="0"><tr><td></td></tr></
table></td></tr><tr><td valign="top"><form><table border="0"
cellpadding="4" bgcolor="a0b8c8" cellspacing="1"><tr><td
bgcolor="eeeeee"><table cellpadding="1" width="100%"
cellspacing="0"><tr><td>Name:</td><td>Type:</td><td>Market:</td><td></
td></tr><tr><td><input size="30" name="s"></td><td><select
name="t"><option selected value="S"> Stocks </option><option
value="E"> ETFs </option><option value="I"> Indices </option><option
value="M"> Mutual Funds </option><option value="F"> Futures </
option></select></td><td><select name="m"><option selected
value="US">U.S. & Canada</option><option value="ALL">World Market</
option></select></td><td><input value="Look Up" type="submit"></td></
tr><tr><td valign="bottom" colspan="4"><small><a href="http://
finance.yahoo.com/exchanges">View supported exchanges</a></small></
td></tr></table></td></tr></table></form><table><tr><td
align="left">2 results for <b>'Dupont'</b> (type=<b>Stocks</b>,
market=<b>U.S. & Canada</b>)</td></result>

Regards, Morton

charles.nadeau

10/13/2006 7:04:00 PM

Morton Goldberg wrote:
> On Oct 13, 2006, at 1:55 PM, charles.nadeau@gmail.com wrote:
>
> > require 'net/http'
> > begin
> > hdoc =
> > Net::HTTP.get(URI.parse('http://finance.yahoo.c...
> > s=Dupont&t=S&m=US'))
> >
> > re = /<TD>(.*)</TD>/
> > if hdoc =~ re
> > print "#{$&}\n"
> > else
> > print "Nothing\n"
> > end
> > end
>
> Whrn I substitute '\/TD' for '/TD' and make the regex case
> insensitive, I get a match. See below:
>
> <code>
> ! /usr/bin/env ruby -w
> require 'net/http'
> hdoc = Net::HTTP.get(URI.parse('http://finance.yahoo.c...
> s=Dupont&t=S&m=US'))
> re = /<TD>(.*)<\/TD>/i ### note changes
> if hdoc =~ re
> puts "#{$&}\n"
> else
> puts "Nothing\n"
> end
> </code>
>
> <result>
> <td><table border="0" cellpadding="6" width="100%"
> cellspacing="0"><tr><td bgcolor="#556f93"><big><b
> style="color:#ffffff">Symbol Lookup </b></big></td></tr></table></
> td></tr><tr><td></td></tr></table></td></tr><tr><td><table
> cellpadding="0" border="0" cellspacing="0"><tr><td></td></tr></
> table></td></tr><tr><td valign="top"><form><table border="0"
> cellpadding="4" bgcolor="a0b8c8" cellspacing="1"><tr><td
> bgcolor="eeeeee"><table cellpadding="1" width="100%"
> cellspacing="0"><tr><td>Name:</td><td>Type:</td><td>Market:</td><td></
> td></tr><tr><td><input size="30" name="s"></td><td><select
> name="t"><option selected value="S"> Stocks </option><option
> value="E"> ETFs </option><option value="I"> Indices </option><option
> value="M"> Mutual Funds </option><option value="F"> Futures </
> option></select></td><td><select name="m"><option selected
> value="US">U.S. & Canada</option><option value="ALL">World Market</
> option></select></td><td><input value="Look Up" type="submit"></td></
> tr><tr><td valign="bottom" colspan="4"><small><a href="http://
> finance.yahoo.com/exchanges">View supported exchanges</a></small></
> td></tr></table></td></tr></table></form><table><tr><td
> align="left">2 results for <b>'Dupont'</b> (type=<b>Stocks</b>,
> market=<b>U.S. & Canada</b>)</td></result>
>
> Regards, Morton

Morton, Aaron,

You are both right, thanks a lot! I also added "m" at the end of the
regular expression to match whatever might span two lines.
Cheers!

Charles
------
http://radio.weblogs.co...
http://charlesnadeau.blo...

charles.nadeau

10/13/2006 7:04:00 PM

comp.lang.ruby

Problem with a regular expression

charles.nadeau

Aaron Patterson

Morton Goldberg

charles.nadeau

charles.nadeau

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