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abhi4.amity has asked for the wisdom of the Perl Monks concerning the following question:

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Re: vertcal tab
by ikegami (Patriarch) on Feb 03, 2011 at 08:37 UTC

    "NOTE: Unlike C and other languages, Perl has no \v escape sequence for the vertical tab (VT - ASCII 11), but you may use \ck or \x0b."

    If it did, \v in string literal would simply include character 0x0B in the resulting string. No more, no less.

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Re: vertcal tab
by GrandFather (Saint) on Feb 03, 2011 at 08:39 UTC

    What is your reason for asking? As it stands your question doesn't make a great deal of sense. Perl doesn't recognise v as an escape character. However the ASCII VT (vertical tab, ctrl-k) character can be generated using \x0b.

    True laziness is hard work
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Re: vertical tab
by davido (Cardinal) on Feb 03, 2011 at 08:44 UTC

    Here's one program, along with its output:

    use strict;
use warnings;
print "Hello\v world.\n"

    [download]

    The output:

    Hellov world.

    [download]

    I think that sums it up.

    Vertical tab, you say? perlop has a section called "Quote and Quote Like Operators", which you should have a look at to understand what escape sequences Perl recognizes.


    Dave

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Re: form feed
by cdarke (Prior) on Feb 03, 2011 at 12:29 UTC
    I noticed that you altered your question. Please, don't do that. If you have a different question then raise a new post.

    Although we welcome questions, this is meant as a Perl forum rather than basic computing questions. Don't push your luck with these questions, I hope you are not going to go through the entire character set.

    A form feed was originally used to throw a new page on a line-printer. On some terminal devices it also cleared the screen. Generally not used much these days.
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Re: vertcal tab
by cdarke (Prior) on Feb 03, 2011 at 08:52 UTC
    It might have been in old versions of Perl, but not any more:
    print "<\v>";

    [download]
    Gives:
    Unrecognized escape \v passed through at C:\gash.pl line 6.
<v>

    [download]
    perl 5.12.0

    Update: I rather like this: http://prog21.dadgum.com/76.html

    Interestingly it is still mentioned in the 5.12.2 version of perlre.
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      perlre seems to be suggesting that regular expressions will recognize \v as vertical whitespace, in text that's being matched. But '\v' as a pattern is not the same as '\v' as a string escape sequence.


      Dave

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Re: form feed
by Old_Gray_Bear (Bishop) on Feb 03, 2011 at 15:09 UTC
    A Form Feed (FF) is a skip-to-channel-twelve command for an IBM line printer. If your printer-control tape does not have a twelve-punch, this is the quickest way to empty a box of continuous form paper....

    ----
    I Go Back to Sleep, Now.

    OGB

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Re: vertcal tab
by elef (Friar) on Feb 03, 2011 at 08:49 UTC
    This sounds an awful lot like homework and doesn't make much sense on top of that. "Send me a program related to a vertical tab"...? What for?
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Re: form feed
by Anonymous Monk on Feb 03, 2011 at 18:13 UTC
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