Freemarker: Can't convert boolean to string automatically, because the "boolean_format" setting was "true,false"

[sunmingtao]

The expression myBool!false?string('A', 'B') causes error

Caused by: freemarker.core._MiscTemplateException: Can't convert boolean to string automatically, because the "boolean_format" setting was "true,false", which is the legacy default computer-language format, and hence isn't accepted.

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Tip: If you just want "true"/"false" result as you are generting computer-language output, use "?c", like ${myBool?c}.
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Tip: You can write myBool?string('yes', 'no') and like to specify boolean formatting in place.
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Tip: If you need the same two values on most places, the programmers should set the "boolean_format" setting to something like "yes,no".
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[sunmingtao]

The !false part causes the problem. Removing it fixes it -- myBool?string('A', 'B')