Thanks again! By reducing to a simpler example, I now see that eval("$x + $y") and eval('$x + $y') are both evaluated by, er, eval. I had played with eval originally because I thought eval($mw->Label(-text => "Col. 1", $opt, -padx => 10)->grid( ...) would substitute $opt with its contents, and in turn evaluate the entire string. I still don't understand the steps the interpreter takes when processing an eval, but it's probably not a fruitful path to pursue further at this time. Better that I understand now that since subroutines take lists as their argument, @opt is an appropriate means to convey list items.

In reply to Re^7: tk option+value in variable? by cniggeler
in thread tk option+value in variable? by cniggeler

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