comment on

I can accept that all code references are callbacks. That's not an expensive check to do.
What should the template engine do if you pass a callback in for a loop variable and the callback returns a scalar after 10 iterations?
Actually, upon thinking about this, I just realized I have a bug in my templating engine in that I don't check to see if the value in the looping array is a hashref. Thanks! :-)
So, if the callback doesn't give the engine what it needs, just treat it like a regular failure. Ok ...
I'm actually thinking that a callback dying is your damn fault, not the engine's. So, the engine shouldn't catch the errors.
Parameters ... the big problem isn't passing them around, it's figuring out how to specify them. I think it's better if you pass in a CODE ref that already has the parameters for your callback specified, at least for now.
I think that eval shouldn't be allowed, period.

Note: While researching this response, I discovered that HTML::Template will do the right thing when passed a CODE reference for a TMPL_VAR or TMPL_IF, just like you want. But, it won't allow a CODE ref for a TMPL_LOOP. I'm sure we could provide a patch for Sam, but I have my own engine to patch. *sighs*

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re^3: Templating algorithm - pass in variables vs callback? by dragonchild
in thread Templating algorithm - pass in variables vs callback? by Tanktalus

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