Sometimes it would be nice to be able to do this, just return None in any expression evaluating for a nonexistent dict key instead of raising KeyError.
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Just catch the error with a try/except statement. – wwii Apr 13 '14 at 21:28
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@wwii: This is a *templating language*, not Python. – Martijn Pieters Apr 13 '14 at 21:42
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Hmm, my bad, sorry about that. ```get()``` is probably the correct response even if it wasn't a template language. – wwii Apr 14 '14 at 06:27
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You'd use dict.get() to access the key instead:
<div tal:attributes="class some_dict.get(some_key)">
where the class attribute would be omitted if some_key is not present, as the default return value from dict.get() is None if the key is missing.
Martijn Pieters
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