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field_maybe_none for participant variables

#1 by nathalie

Hi everyone,

does field_maybe_none work for participant variables, too? I want to check whether they are empty (specifically:  player.field_maybe_none('participant.field') is not None)

I tried player.field_maybe_none('participant.field') and player.participant.field_maybe_none('field') but both return an error. 

Thank you for helping!

#2 by gr0ssmann

I usually do

    "fieldname" in player.participant.vars

So, for example:

    if "bonus" not in player.participant.vars:
        player.participant.vars["bonus"] = 0

However, typically I'd say this is an "anti-pattern"; I would always ensure at the beginning that fields have some default or initial value set.

#3 by Fanist

I agree with @gr0ssmann that it is better to set some initial values. For example, you can set "gender" to be -99 if no other rewriting is triggered, and let gender==-99 be the signal that the field is none.

#4 by nathalie

Thank you! That worked :-)

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