Item Parameters
For an item to work with different values, the values must be passed in. These values are called item parameters.
There are a number of related concepts:
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User needs to be able to specify how the values are defined: - Plain Values: Use a value provided by the user.
- Referenced Values: Use a value produced by a predecessor item.
- Transformed Values: Take values produced by predecessor item(s), transform it, then use that.
 
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Implementors: - Need to define the parameters.
- Take in parameter values for state_current,state_goal.
- Take in Option<Field>for each field within the parameter fortry_state_current,try_state_goal.
 
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Peace should be able to store and load: - The specification by the user.
- The actual values computed and used during command execution.