I'm currently in a situation in which I need to create variables whose names are determined by other variable values. (this is to support older code which relies on those variables having those names while moving to a new architecture in which the info is stored in a db.

I have:

my $test="my_variable_name"; #imagine this is a hash key
my $default_value="the value I set"; #while this is the hash value
eval("\$$test = '$default_value';");
print "the value of \$my_variable_name = $my_variable_name\n";
$my_variable_name = "A new value";
print "the value of \$my_variable_name = $my_variable_name\n";

[download]

So far, so good. That works.

I'm fairly certain that there is a Better(tm) way to do this using symbol table manipulation, but I'm not sure how to go about it. I've tried all of:

my $test="my_variable_name";
my $default_value="the value I set";
*$test = $default_value;
#*{$test} = $default_value;
#*{"$test"} = $default_value;
#*{"$test"} = \$default_value;
#*{"$test"} = \&default_value;
print "the value of \$my_variable_name = $my_variable_name\n";
$my_variable_name = "A new value";
print "the value of \$my_variable_name = $my_variable_name\n";

[download]

none of which work. (all commented lines have been tried).

Any pointers would be appreciated. Thanks

In reply to symbol table vs. eval by Anonymous Monk

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