Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl-Sensitive Sunglasses
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??
Let's have a look at the '\', '[]' and '()' constructs:
  • [$a, $b, $c] is a reference to an array with three scalar elements.
  • \[$a, $b, $c] is a reference to a scalar, which againg is a reference to an array with three scalar elements.
  • [\$a, \$b, \$c] is a reference to an array with three scalars. Each of theese three scalars is a reference to the real scalar.
So using the special braces '[' and ']' creates a reference to an array. If you use the normal braces '(' and ')' you group things into lists, so:
  • ($a, $b, $c) is a list of three scalar elements. It is not an array, but a list.
  • \($a, $b, $c) is a list of three scalar elemnts. Each of theese three elements is a reference to the real scalar (that is your value "foo", "bar" and "baz")
  • (\$a, \$b, \$c) is excatly the same as \($a, $b, $c). The '\' operator will distribute over the list.
So if we use the [$a, $b, $c] construct our list @list will contain one element, namely a reference to an array. If we on the other hand use the ($a, $b, $c) construct, the list will contain 3 elements.

So then, an easier way to write [\$a, \$b, \$c] would be [ \($a, $b, $c) ]. But still, this will not fix your example - I hope you can see the error in the example, but let's fix it:

$a = "foo"; $b = "bar"; $c = "baz"; @list = \($a, $b, $c); foreach(@list) { print $$_ . "\n"; }
Autark.

In reply to RE: \($a, $b, $c) eq (\$a, \$b, \$c), is \$a, $b, $c eq \$a, \$b, \$c? by autark
in thread \($a, $b, $c) eq (\$a, \$b, \$c), is \$a, $b, $c eq \$a, \$b, \$c? by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others chanting in the Monastery: (7)
As of 2024-03-28 13:53 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found