I have a program where I let the user specify some expressions using variables in the program. For now I want to use strings like "foo has the value $foo" and see the value of $foo printed out. My code looks like this: 
sub fun{
 return sub {return 'foo has value $foo');
}
...
$coderef = fun;
$foo = 7;

$str = &$coderef;

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Of course, $str is "foo has the value $foo". I'd like to do "variable interpolation" on $str. I thought eval might do that, but is unhappy trying to do just that. I believe that there is a simple answer, but it is one of those days when the mind gets totally fogged...

When I tried double quotes around the string, it tried to evaluate $foo (which was undefined) and created a closure with the string having an undefined value.

As always, any help is appreciated,
--traveler

In reply to Delaying interpolation by traveler

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