perlquestion
Anonymous Monk
Suppose I have a hash whose values are anonymous functions,
e.g.,
<CODE>
%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'};
</CODE>
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.
<CODE>
while(<>) {
$func = $_;
chomp($func);
$func = uc($func);
if( defined($functions{$func}) ) {
### insert code here to execute function in hash ###
}
else {
print "\"$func\" not defined\n";
}
}
</CODE>
My question is this. At the spot to insert the code to
execute the function, I would like to do this:
<CODE>
&$functions{$func};
</CODE>
but perl won't let me. I have found that if I do this:
<CODE>
my $code;
$code = $functions{$func};
&$code;
</CODE>
it works. Why doesn't the first work?
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