Beefy Boxes and Bandwidth Generously Provided by pair Networks
P is for Practical
 
PerlMonks  

Comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
Suppose I have a hash whose values are anonymous functions, e.g.,
%functions = ( '?' => 0, 'HELLO' => sub { print "Hello, world.\n" }, 'HELP' => sub { print "Type 'hello' or 'goodbye'\n" }, 'GOODBYE' => sub { print "Goodbye...\n"; exit(0) } ); # have to initialize this outside declaration of %functions $functions{'?'} = $functions{'HELP'};
Then, suppose I want to take input from the user and see if the things the user types are keys in the hash. If so, I execute the associated function.
while(<>) { $func = $_; chomp($func); $func = uc($func); if( defined($functions{$func}) ) { ### insert code here to execute function in hash ### } else { print "\"$func\" not defined\n"; } }
My question is this. At the spot to insert the code to execute the function, I would like to do this:
&$functions{$func};
but perl won't let me. I have found that if I do this:
my $code; $code = $functions{$func}; &$code;
it works. Why doesn't the first work?

In reply to using a hash of functions 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":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and all is quiet...

    How do I use this? | Other CB clients
    Other Users?
    Others rifling through the Monastery: (6)
    As of 2018-07-16 03:18 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?
      It has been suggested to rename Perl 6 in order to boost its marketing potential. Which name would you prefer?















      Results (330 votes). Check out past polls.

      Notices?