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Perl-Users Digest, Issue: 3186 Volume: 11

daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Fri Oct 22 03:09:24 2010

Date: Fri, 22 Oct 2010 00:09:07 -0700 (PDT)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)

Perl-Users Digest           Fri, 22 Oct 2010     Volume: 11 Number: 3186

Today's topics:
    Re: Formatting to delete leading zeroes <glennj@ncf.ca>
    Re: Formatting to delete leading zeroes <uri@StemSystems.com>
    Re: Formatting to delete leading zeroes <tadmc@seesig.invalid>
        map an array but first item different? <justin.1010@purestblue.com>
    Re: map an array but first item different? (Randal L. Schwartz)
        on windows 7 / cygwin / perl / cpan - cannot make cpan  <emailsrvr-groups@yahoo.com>
    Re: on windows 7 / cygwin / perl / cpan - cannot make c <sherm.pendley@gmail.com>
        Posting Guidelines for comp.lang.perl.misc ($Revision:  tadmc@seesig.invalid
        Proposal: Using the debugger or 'diagnostics' should pr <w.c.humann@arcor.de>
    Re: Proposal: Using the debugger or 'diagnostics' shoul <nospam-abuse@ilyaz.org>
        Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)

----------------------------------------------------------------------

Date: 21 Oct 2010 10:31:02 GMT
From: Glenn Jackman <glennj@ncf.ca>
Subject: Re: Formatting to delete leading zeroes
Message-Id: <slrnic05j8.n91.glennj@smeagol.ncf.ca>

At 2010-10-20 05:26PM, "Uri Guttman" wrote:
> >>>>> "GJ" == Glenn Jackman <glennj@ncf.ca> writes:
>  
>   GJ> At 2010-10-20 04:38PM, "junior@iam.invalid" wrote:
>   >> How do I use sprintf() to delete a leading zero before the decimal point?
>   >> 
>   >> E.g., $num = 0.25 and I want $num = .25. I don't want to delete any
>   >> posiive integers, only the zero if there's no positive integer, i.e., 9.54
>   >> shows as 9.54, but 0.54 shows as .54.
>  
>   GJ> What you asked for
>   GJ>     $num =~ s/^0\././;
>  
>  why replace the . with a .?

So "0.25" does not become "25"
The OP specified "delete a leading zero before the decimal point.

-- 
Glenn Jackman
    Write a wise saying and your name will live forever. -- Anonymous


------------------------------

Date: Thu, 21 Oct 2010 12:19:07 -0400
From: "Uri Guttman" <uri@StemSystems.com>
Subject: Re: Formatting to delete leading zeroes
Message-Id: <87zku7fric.fsf@quad.sysarch.com>

>>>>> "GJ" == Glenn Jackman <glennj@ncf.ca> writes:

  GJ> At 2010-10-20 05:26PM, "Uri Guttman" wrote:
  >> >>>>> "GJ" == Glenn Jackman <glennj@ncf.ca> writes:
  >> 
  GJ> At 2010-10-20 04:38PM, "junior@iam.invalid" wrote:
  >> >> How do I use sprintf() to delete a leading zero before the decimal point?
  >> >> 
  >> >> E.g., $num = 0.25 and I want $num = .25. I don't want to delete any
  >> >> posiive integers, only the zero if there's no positive integer, i.e., 9.54
  >> >> shows as 9.54, but 0.54 shows as .54.
  >> 
  GJ> What you asked for
  GJ> $num =~ s/^0\././;
  >> 
  >> why replace the . with a .?

  GJ> So "0.25" does not become "25"
  GJ> The OP specified "delete a leading zero before the decimal point.

so? the code i posted and your second one did that just fine. just
deleting leading zeroes is enough. deleting the . and then replacing it
is extra work.

uri

-- 
Uri Guttman  ------  uri@stemsystems.com  --------  http://www.sysarch.com --
-----  Perl Code Review , Architecture, Development, Training, Support ------
---------  Gourmet Hot Cocoa Mix  ----  http://bestfriendscocoa.com ---------


------------------------------

Date: Thu, 21 Oct 2010 13:24:44 -0500
From: Tad McClellan <tadmc@seesig.invalid>
Subject: Re: Formatting to delete leading zeroes
Message-Id: <slrnic11jr.d9i.tadmc@tadbox.sbcglobal.net>

Uri Guttman <uri@StemSystems.com> wrote:
>>>>>> "GJ" == Glenn Jackman <glennj@ncf.ca> writes:
>
>  GJ> At 2010-10-20 05:26PM, "Uri Guttman" wrote:
>  >> >>>>> "GJ" == Glenn Jackman <glennj@ncf.ca> writes:
>  >> 
>  GJ> At 2010-10-20 04:38PM, "junior@iam.invalid" wrote:
>  >> >> How do I use sprintf() to delete a leading zero before the decimal point?
>  >> >> 
>  >> >> E.g., $num = 0.25 and I want $num = .25. I don't want to delete any
>  >> >> posiive integers, only the zero if there's no positive integer, i.e., 9.54
>  >> >> shows as 9.54, but 0.54 shows as .54.
>  >> 
>  GJ> What you asked for
       ^^^^^^^^^^^^^^^^^^
       ^^^^^^^^^^^^^^^^^^
>  GJ> $num =~ s/^0\././;
>  >> 
>  >> why replace the . with a .?
>
>  GJ> So "0.25" does not become "25"
>  GJ> The OP specified "delete a leading zero before the decimal point.
>
> so? 


So, what the OP wanted when there was a leading zero that was *not*
before the decimal point was left unspecified.


> just
> deleting leading zeroes is enough. 


But that is not what was asked for.

I expect that Glenn's point was that the OP's spec may have
been an XY problem, where he wanted to delete leading zeros
(so he gave code to do that), or the spec may have been literal
(so he gave code to do that too).


-- 
Tad McClellan
email: perl -le "print scalar reverse qq/moc.liamg\100cm.j.dat/"
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.


------------------------------

Date: Thu, 21 Oct 2010 16:38:53 +0100
From: Justin C <justin.1010@purestblue.com>
Subject: map an array but first item different?
Message-Id: <dd36p7-q55.ln1@zem.masonsmusic.co.uk>

I'm using CGI.pm to generate a table, and within that table I'm using
map to put the contents of an arrayref into cells within each table row:

print table(
	{ get_formatting_string($formatting) }, 
	Tr({-class=>'holding'},
		[
			th([@{$col_heads}]), 
			map { td($_) } @{$data},
		], 
	), 
);

Here's what Data::Dumper says about $data:
$VAR1 = [ '2010-10-01', 'First consignment of two. Order split due to size.', 'John Smith' ]; 
$VAR2 = [ '2010-10-21', 'Sent email requesting payment. If no joy by follow-up date then set a deadline.', 'Justin' ]; 

The problem I'm having is that when the second column has a lot of text
it causes the first column to shrink and wrap and this looks terrible. I
can fix this with td({-nowrap=>'nowrap}, $_) if doing things manually,
but I'd still like map to handle this for me because I'm using the same
sub to print tables with different numbers of columns.

How can I set a parameter for the first item while still letting map
handle this? ... or how else could I do this?

Thanks for any help you can give with this.

   Justin.

-- 
Justin C, by the sea.


------------------------------

Date: Thu, 21 Oct 2010 09:45:18 -0700
From: merlyn@stonehenge.com (Randal L. Schwartz)
Subject: Re: map an array but first item different?
Message-Id: <86r5fjsdep.fsf@red.stonehenge.com>

>>>>> "Justin" == Justin C <justin.1010@purestblue.com> writes:

Justin> print table(
Justin> 	{ get_formatting_string($formatting) }, 
Justin> 	Tr({-class=>'holding'},
Justin> 		[
Justin> 			th([@{$col_heads}]), 
Justin> 			map { td($_) } @{$data},
Justin> 		], 
Justin> 	), 
Justin> );

 ...

Justin> How can I set a parameter for the first item while still letting map
Justin> handle this? ... or how else could I do this?

Just use an aux counter:

my $n = 0;
print table( { ... },
        Tr({ ... },
          [
            th(..),
            map {
              if (++$n == 1) {
                 do your thing for first item
              } else {
                 do your thing for remaining items
              }
            } @$data,
          ],
        ),
      );

By the way, I think td($data) would have avoided the map.  Been a while
since I hacked CGI.pm though.

print "Just another Perl hacker,"; # the original

-- 
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn@stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Smalltalk/Perl/Unix consulting, Technical writing, Comedy, etc. etc.
See http://methodsandmessages.posterous.com/ for Smalltalk discussion


------------------------------

Date: Thu, 21 Oct 2010 07:51:51 -0700 (PDT)
From: SVCitian <emailsrvr-groups@yahoo.com>
Subject: on windows 7 / cygwin / perl / cpan - cannot make cpan work
Message-Id: <7c947a81-4f0b-4e79-a801-1e28bbead43c@v20g2000prl.googlegroups.com>

Hi, I have tried load some Perl Modules using CPAN.. but I can't make
it work.

fyi, curl "http://..." works on the command line perfectly. (just so
that you know the internet connection is all ok.

this is what i see on the cpan.. when i do install... what can i do to
fix this issue.

I use Windows 7, Cygwin, Cpan with all the Perl Stuff installed...
wget, lynx, curl, ftp, and all the required stuff are there.


cpan[1]> install HTML::TableExtract
CPAN: Storable loaded ok (v2.20)
CPAN: LWP::UserAgent loaded ok (v5.835)
CPAN: Time::HiRes loaded ok (v1.9719)
Warning: no success downloading '/home/John/.cpan/sources/authors/
01mailrc.txt.g
z.tmp2728'. Giving up on it. at /usr/lib/perl5/5.10/CPAN/Index.pm line
225
Fetching with LWP:
  http://www.perl.org/CPAN/authors/01mailrc.txt.gz
LWP failed with code[502] message[Bad Gateway]

Trying with "/usr/bin/curl -L -f -s -S --netrc-optional" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
curl: (22) The requested URL returned error: 502

    Function system("/usr/bin/curl -L -f -s -S --netrc-optional
"http://www.perl
 .org/CPAN/authors/01mailrc.txt.gz"  > /home/John/.cpan/sources/authors/
01mailrc.
txt.tmp2728")
    returned status 22 (wstat 5632)
Warning: expected file [/home/John/.cpan/sources/authors/
01mailrc.txt.gz.tmp2728
] doesn't exist

Trying with "/usr/bin/wget -O /home/John/.cpan/sources/authors/
01mailrc.txt.tmp2
728" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
--2010-10-21 21:47:43--  http://www.perl.org/CPAN/authors/01mailrc.txt.gz
Resolving www.perl.org (www.perl.org)... 207.171.7.63
Connecting to www.perl.org (www.perl.org)|207.171.7.63|:80...
connected.
HTTP request sent, awaiting response... 502 Bad Gateway
2010-10-21 21:47:44 ERROR 502: Bad Gateway.


    Function system("/usr/bin/wget -O /home/John/.cpan/sources/authors/
01mailrc.
txt.tmp2728 "http://www.perl.org/CPAN/authors/01mailrc.txt.gz" ")
    returned status 8 (wstat 2048)
Warning: expected file [/home/John/.cpan/sources/authors/
01mailrc.txt.gz.tmp2728
] doesn't exist

Trying with "/usr/bin/lynx -source" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
CPAN: Compress::Zlib loaded ok (v2.02)
Error while trying to rename '/home/John/.cpan/sources/authors/
01mailrc.txt.gz.t
mp2728' to '/home/John/.cpan/sources/authors/01mailrc.txt.gz': No such
file or d
irectoryWarning: no success downloading '/home/John/.cpan/sources/
authors/01mail
rc.txt.gz.tmp2728'. Giving up on it. at /usr/lib/perl5/5.10/CPAN/
Index.pm line 2
25
Fetching with LWP:
  http://www.perl.org/CPAN/authors/01mailrc.txt.gz
LWP failed with code[502] message[Bad Gateway]

Trying with "/usr/bin/curl -L -f -s -S --netrc-optional" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
curl: (22) The requested URL returned error: 502

    Function system("/usr/bin/curl -L -f -s -S --netrc-optional
"http://www.perl
 .org/CPAN/authors/01mailrc.txt.gz"  > /home/John/.cpan/sources/authors/
01mailrc.
txt.tmp2728")
    returned status 22 (wstat 5632)
Warning: expected file [/home/John/.cpan/sources/authors/
01mailrc.txt.gz.tmp2728
] doesn't exist

Trying with "/usr/bin/wget -O /home/John/.cpan/sources/authors/
01mailrc.txt.tmp2
728" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
--2010-10-21 21:47:51--  http://www.perl.org/CPAN/authors/01mailrc.txt.gz
Resolving www.perl.org (www.perl.org)... 207.171.7.63
Connecting to www.perl.org (www.perl.org)|207.171.7.63|:80...
connected.
HTTP request sent, awaiting response... 502 Bad Gateway
2010-10-21 21:47:52 ERROR 502: Bad Gateway.


    Function system("/usr/bin/wget -O /home/John/.cpan/sources/authors/
01mailrc.
txt.tmp2728 "http://www.perl.org/CPAN/authors/01mailrc.txt.gz" ")
    returned status 8 (wstat 2048)
Warning: expected file [/home/John/.cpan/sources/authors/
01mailrc.txt.gz.tmp2728
] doesn't exist

Trying with "/usr/bin/lynx -source" to get
    "http://www.perl.org/CPAN/authors/01mailrc.txt.gz"
Error while trying to rename '/home/John/.cpan/sources/authors/
01mailrc.txt.gz.t
mp2728' to '/home/John/.cpan/sources/authors/01mailrc.txt.gz': No such
file or d
irectoryLockfile removed.



------------------------------

Date: Thu, 21 Oct 2010 11:55:58 -0400
From: Sherm Pendley <sherm.pendley@gmail.com>
Subject: Re: on windows 7 / cygwin / perl / cpan - cannot make cpan work
Message-Id: <m2wrpbo7zl.fsf@sherm.shermpendley.com>

SVCitian <emailsrvr-groups@yahoo.com> writes:

> Hi, I have tried load some Perl Modules using CPAN.. but I can't make
> it work.
>
> fyi, curl "http://..." works on the command line perfectly. (just so
> that you know the internet connection is all ok.

Yeah, the error messages seem to indicate that the request is being
made OK, but the server is returning an error - i.e. connectivity doesn't
seem to be the problem.

Have you tried configuring CPAN.pm to use a different mirror site?

sherm--

-- 
Sherm Pendley
                                   <http://camelbones.sourceforge.net>
Cocoa Developer


------------------------------

Date: Fri, 22 Oct 2010 02:05:27 -0500
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.9 $)
Message-Id: <Q-GdnblCwKEqqlzRnZ2dnUVZ5omdnZ2d@giganews.com>

Outline
   Before posting to comp.lang.perl.misc
      Must
       - Check the Perl Frequently Asked Questions (FAQ)
       - Check the other standard Perl docs (*.pod)
      Really Really Should
       - Lurk for a while before posting
       - Search a Usenet archive
      If You Like
       - Check Other Resources
   Posting to comp.lang.perl.misc
      Is there a better place to ask your question?
       - Question should be about Perl, not about the application area
      How to participate (post) in the clpmisc community
       - Carefully choose the contents of your Subject header
       - Use an effective followup style
       - Speak Perl rather than English, when possible
       - Ask perl to help you
       - Do not re-type Perl code
       - Provide enough information
       - Do not provide too much information
       - Do not post binaries, HTML, or MIME
      Social faux pas to avoid
       - Asking a Frequently Asked Question
       - Asking a question easily answered by a cursory doc search
       - Asking for emailed answers
       - Beware of saying "doesn't work"
       - Sending a "stealth" Cc copy
      Be extra cautious when you get upset
       - Count to ten before composing a followup when you are upset
       - Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------

Posting Guidelines for comp.lang.perl.misc ($Revision: 1.9 $)
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        One such searchable archive is:

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Posting to comp.lang.perl.misc
    There can be 200 messages in clpmisc in a single day. Nobody is going to
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        Show the output (including the verbatim text of any messages) of
        your program.

        Describe how you want the output to be different from what you are
        getting.

        If you have no idea at all of how to code up your situation, be sure
        to at least describe the 2 things that you *do* know: input and
        desired output.

    Do not provide too much information
        Do not just post your entire program for debugging. Most especially
        do not post someone *else's* entire program.

    Do not post binaries, HTML, or MIME
        clpmisc is a text only newsgroup. If you have images or binaries
        that explain your question, put them in a publically accessible
        place (like a Web server) and provide a pointer to that location. If
        you include code, cut and paste it directly in the message body.
        Don't attach anything to the message. Don't post vcards or HTML.
        Many people (and even some Usenet servers) will automatically filter
        out such messages. Many people will not be able to easily read your
        post. Plain text is something everyone can read.

  Social faux pas to avoid
    The first two below are symptoms of lots of FAQ asking here in clpmisc.
    It happens so often that folks will assume that it is happening yet
    again. If you have looked but not found, or found but didn't understand
    the docs, say so in your article.

    Asking a Frequently Asked Question
        It should be understood that you may have missed the applicable FAQ
        when you checked, which is not a big deal. But if the Frequently
        Asked Question is worded similar to your question, folks will assume
        that you did not look at all. Don't become indignant at pointers to
        the FAQ, particularly if it solves your problem.

    Asking a question easily answered by a cursory doc search
        If folks think you have not even tried the obvious step of reading
        the docs applicable to your problem, they are likely to become
        annoyed.

        If you are flamed for not checking when you *did* check, then just
        shrug it off (and take the answer that you got).

    Asking for emailed answers
        Emailed answers benefit one person. Posted answers benefit the
        entire community. If folks can take the time to answer your
        question, then you can take the time to go get the answer in the
        same place where you asked the question.

        It is OK to ask for a *copy* of the answer to be emailed, but many
        will ignore such requests anyway. If you munge your address, you
        should never expect (or ask) to get email in response to a Usenet
        post.

        Ask the question here, get the answer here (maybe).

    Beware of saying "doesn't work"
        This is a "red flag" phrase. If you find yourself writing that,
        pause and see if you can't describe what is not working without
        saying "doesn't work". That is, describe how it is not what you
        want.

    Sending a "stealth" Cc copy
        A "stealth Cc" is when you both email and post a reply without
        indicating *in the body* that you are doing so.

  Be extra cautious when you get upset
    Count to ten before composing a followup when you are upset
        This is recommended in all Usenet newsgroups. Here in clpmisc, most
        flaming sub-threads are not about any feature of Perl at all! They
        are most often for what was seen as a breach of netiquette. If you
        have lurked for a bit, then you will know what is expected and won't
        make such posts in the first place.

        But if you get upset, wait a while before writing your followup. I
        recommend waiting at least 30 minutes.

    Count to ten after composing and before posting when you are upset
        After you have written your followup, wait *another* 30 minutes
        before committing yourself by posting it. You cannot take it back
        once it has been said.

AUTHOR
    Tad McClellan and many others on the comp.lang.perl.misc newsgroup.

-- 
Tad McClellan
email: perl -le "print scalar reverse qq/moc.liamg\100cm.j.dat/"
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.


------------------------------

Date: Thu, 21 Oct 2010 04:29:40 -0700 (PDT)
From: Wolfram Humann <w.c.humann@arcor.de>
Subject: Proposal: Using the debugger or 'diagnostics' should preload Carp::Heavy
Message-Id: <860d831f-75c0-44ad-9196-10d2ad713d61@26g2000yqv.googlegroups.com>

When perl runs using the debugger or if you "use diagnostics", (some?)
compile time errors will be hidden by an error from Carp::Heavy.

Example:
> perl -E'use strict; $num = 17'
Global symbol "$num" requires explicit package name at -e line 1.
Execution of -e aborted due to compilation errors.

> perl -E'use diagnostics "-t"; use strict; $num = 17'
BEGIN not safe after errors--compilation aborted at /home/wolframh/
perl/perl5.10.1/lib/5.10.1/Carp/Heavy.pm line 11.
Compilation failed in require at /home/wolframh/perl/perl5.10.1/lib/
5.10.1/Carp.pm line 33.

> perl -E'use Carp::Heavy; use diagnostics "-t"; use strict; $num = 17'
Uncaught exception from user code:
        Global symbol "$num" requires explicit package name at -e line
1.
Execution of -e aborted due to compilation errors.
 at -e line 1

In the first example, the problem with $num is reported correctly.
The second example reports an error in Carp::Heavy -- even though the
problem is still $num. This can be verified by adding 'my' before
$num: the error message goes away. The same misguiding error message
happens with
> perl -d -E'use strict; $num = 12'
This effect has been reported by many people at various places. Use a
websearch for '"failed in require" "carp heavy"' to see some. The
replies often tell pepole how to correct their code and make the error
message go away but it would be better if they got a decent error
message in the first place so they can fix their bugs without external
help :-)
The most helpful reply I found was from Ilya Zakharevich at
http://groups.google.com/group/comp.lang.perl.misc/msg/efa2d9659eb48e90.
This told me that the error message from Carp::Heavy goes away and the
*real* error message reappears, when Carp is fully loaded (i.e.
ncluding Carp::Heavy) before the error occurs. The third example shows
that this is indeed the case.

While in "normal" code it makes sense to defer loading Carp::Heavy
until it's really required (e.g. in production code, the probabilty of
an error occurring that needs to reported should be low), this is not
the case with the debugger or "use diagnostics":
a) the probability is high that Carp::Heavy will be loaded anyway is
high
b) in such a "bug hunting" scenario, the annoyance of a misleading
error message by far outweighs a few extra milliseconds of startup
time.

I would therefore propose, that the debugger and "use diagostics" do a
"use Carp::Heavy" internally. What do you think?
Wolfram


------------------------------

Date: Thu, 21 Oct 2010 18:01:28 +0000 (UTC)
From: Ilya Zakharevich <nospam-abuse@ilyaz.org>
Subject: Re: Proposal: Using the debugger or 'diagnostics' should preload Carp::Heavy
Message-Id: <slrnic0vvo.iua.nospam-abuse@powdermilk.math.berkeley.edu>

On 2010-10-21, Wolfram Humann <w.c.humann@arcor.de> wrote:
> I would therefore propose, that the debugger and "use diagostics" do a
> "use Carp::Heavy" internally. What do you think?

Essentially, this would debug different code than the original one.  A
no-no-no.

A better thing would be to catch in Carp the errors in loading
Carp::Heavy, and emit the advice to preload Carp::Heavy.

Hope this helps,
Ilya


------------------------------

Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin) 
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>


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