Set the session variable
-- the value to set the session variable to
Perform an atomic update of this Settable.
Different Vars require different mechanisms for synchronization.
Change the value of the Var for the lifespan of the function
Generate a function that will take a snapshot of the current RequestVars such that they can be restored
Shadow of the 'is' method
The current value of the variable
This defines whether or not Lift will log when a RequestVar is set but then not read within the same request cycle.
On any change to this Var, invoke the function.
the function to execute on change
Perform an atomic operation on the Settable.
Shadow of the apply method
Set the Var if it has not been calculated
Has this Var been set or accessed and had its default value calculated
Return a function that, when applied, will set the value of the RequestVar to its current value
Is this RequestVar a member of a snapshot group? If so, specify the group here
A non-side-effecting test if the value was initialized
Applies the given function to the contents of this variable and sets the variable to the resulting value.
-- the function to apply and set the result from.