in reply to why qw() rather than ()

AFIC, qw() allows you to separate the entries with whitespace. That's pretty convenient. Look at this: 
$ perl -e 'print join(", ",qw(1 3 6 2));'
1, 3, 6, 2

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But trying that without the qw gives: 
[jeroen@rulffk]  perl -e 'print join(", ",(1 3 6 2));'
Number found where operator expected at -e line 1, near "1 3"
    (Missing operator before  3?)
syntax error at -e line 1, near "1 3"
Number found where operator expected at -e line 1, near "3 6"
    (Missing operator before  6?)
Number found where operator expected at -e line 1, near "6 2"
    (Missing operator before  2?)
Execution of -e aborted due to compilation errors.

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Hope this helps.

Jeroen
"We are not alone"(FZ)

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Re: Re: why qw() rather than ()
by arhuman (Vicar) on Jan 22, 2001 at 18:30 UTC
    Ok ! thanks for the answer ! I've totally miss the separator problem !

    So, if I've understood

    use Digest::MD5  qw(md5 md5_hex md5_base64);

    is exactly the same as

    use Digest::MD5(md5,md5_hex,md5_base64);


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[d/l]
[select]
      Well, if you add a space after MD5 ;-).

      But that's not the whole thing. From the manpage: 

      =item qw/STRING/

Returns a list of the words extracted out of STRING, using embedded
whitespace as the word delimiters.  It is exactly equivalent to

    split(' ', q/STRING/);

Some frequently seen examples:

    use POSIX qw( setlocale localeconv )
    @EXPORT = qw( foo bar baz );

A common mistake is to try to separate the words with comma or to put
comments into a multi-line qw-string.  For this reason the C<-w>
switch produce warnings if the STRING contains the "," or the "#"
character.

      [download]
      So, there is a difference, although small.

      Jeroen
      "We are not alone"(FZ)

[reply]
[d/l]
      No.

      Using strict would point out the error for you.

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