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Re: Re: Need a better way to count input lines

by Theo (Priest)
on May 07, 2004 at 19:53 UTC ( #351583=note: print w/ replies, xml ) Need Help??


in reply to Re: Need a better way to count input lines
in thread Need a better way to count input lines

That looks a lot more perlish!. I changed it slightly to use the same data in an external file & I get an error for each line of the file that has a "/". (Of course, to get those errors I uncommented the 'no warnings' line)

Last First Phone Bldg Room email Use of uninitialized value in printf at PL.pl line 11, <FH> line 2. Use of uninitialized value in printf at PL.pl line 11, <FH> line 2. Use of uninitialized value in printf at PL.pl line 11, <FH> line 2. ---- Use of uninitialized value in printf at PL.pl line 11, <FH> line 5. Use of uninitialized value in printf at PL.pl line 11, <FH> line 5. Use of uninitialized value in printf at PL.pl line 11, <FH> line 5. john Use of uninitialized value in printf at PL.pl line 11, <FH> line 8. Use of uninitialized value in printf at PL.pl line 11, <FH> line 8. Use of uninitialized value in printf at PL.pl line 11, <FH> line 8. ed@a.nl Use of uninitialized value in printf at PL.pl line 11, <FH> line 11. Use of uninitialized value in printf at PL.pl line 11, <FH> line 11. Use of uninitialized value in printf at PL.pl line 11, <FH> line 11. cbest
If I redirect the output to a file, it looks like this:
Last First Phone Bldg Room email Alanon Bart^M ---- O'Lewis John.^M john Le Much Bo Jo^M ed@a.nl Abe-Jen Mar-Jo^M cbest
The file, as I ran it is:
#!/opt/bin/perl -slw use strict; print "\nLast First Phone Bldg Room email\n"; open FH => "<testdata.txt" or die "can't find the data file: $!\n"; until( eof( FH ) ) { # no warnings 'uninitialized'; printf '%-7.7s %-7.7s ', <FH> =~ m[ ([^,]+) , \s* (.+) $]x +; printf '%7.7s %7.7s %7.7s ', <FH> =~ m[ ([^/]+) / (?:(\S+)\s+) +? (\S+) $]x; printf "%s\n", <FH> =~ m[^(\S+)]; }
I definitely don't understand what's happening in the second half of the middle regexp.

-Theo-
(so many nodes and so little time ... )


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Re: Re: Re: Need a better way to count input lines
by BrowserUk (Pope) on May 07, 2004 at 20:57 UTC

    Weird! The ^Ms that are getting left behind on the end of the first names suggests that the contents of the data file is weird, though given the source that's no real surprise.

    The reason for having the no warnings 'uninitialized' is to avoid the need for a special case to deal with location lines that don't contain the room number. The regex is saying:

    m[ ([^/]+) / # capture the phone number before the slash (?: #optionally capture the room number if it is exists (\S+) # capture all the non-spaces between the / \s+ #and one or more spaces )? # but only if there are two sets of non-spaces # separated by a one or more spaces before EOL (\S+) #capture the building code. $ ]x;

    If the room number isn't present, the second capture ($2) will be undefined, hence the need to suppress the warning. However, that you are getting three warnings means that all 3 captures are undefined (ie. the regex failed to match), which suggests that the data in the file is formatted somewhat differently to the sample data you posted.

    Without being able to see the actual contents of the file it is a little difficult to diagnose the problem.

    Perhaps you could run this one liner on the data file to dump the first few lines in hex and post the output here?

    perl -nle" exit if $. == 15; print unpack 'H*', $_" testdata.txt

    Examine what is said, not who speaks.
    "Efficiency is intelligent laziness." -David Dunham
    "Think for yourself!" - Abigail
      OK, BrowserUk, here are the results.
      %perl -nle" exit if $. == 15; print unpack 'H*', $_" testdata.txt Illegal variable name.
      Hope you can make sense of it ...

      -Theo-
      (so many nodes and so little time ... )

        Are you using linux or cygwin?

        As you were processing Word data, I (stupidly) assumed that you were using Win32 (native). Try

        perl -nle' exit if $. == 15; print unpack "H*", $_' testdata.txt

        Examine what is said, not who speaks.
        "Efficiency is intelligent laziness." -David Dunham
        "Think for yourself!" - Abigail

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