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ATM, there is one possible value for a return type:

int

Parses the value using C#'s int.Parse. Returns the value without any quotes.

long

Parses the value using C#'s long.Parse. Returns the value without any quotes.

bool

If the value output by a value field is a bit (0 or 1) or a string ("true" or "false") then these values are converted to true or false.

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