Set the session variable
Set the session variable
-- the value to set the session variable to
Perform an atomic update of this Settable.
Perform an atomic update of this Settable. The current value is passed to the function and the ValueHolder is set to the result of the function. This is enclosed in the performAtomicOperation method which will, by default, synchronize this instance
Different Vars require different mechanisms for synchronization.
Different Vars require different mechanisms for synchronization. This method implements the Var specific synchronization mechanism
Change the value of the Var for the lifespan of the function
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
Shadow of the 'is' method
The current value of the variable
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.
This defines whether or not Lift will log when a RequestVar is set but then not read within the same request cycle. Change this to false to turn off logging. Logging can also be turned off globally via LiftRules.logUnreadRequestVars.
LiftRules#logUnreadRequestVars
Perform an atomic operation on the Settable.
Perform an atomic operation on the Settable. By default synchronizes the instance, but it could use other mechanisms
Shadow of the apply method
Shadow of the apply method
Set the Var if it has not been calculated
Set the Var if it has not been calculated
Has this Var been set or accessed and had its default value 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
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.
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.
A typesafe container for data with a lifetime nominally equivalent to the lifetime of a page rendered by an HTTP request. RequestVars maintain their value throughout the duration of the current HTTP request and any callbacks for servicing AJAX calls associated with the rendered page. RequestVar instances have no value at the beginning of request servicing (excluding AJAX callbacks) and their value is discarded at the end of request processing. They are commonly used to share values across many snippets. Basic usage:
object MySnippetCompanion { object myRequestVar extends RequestVar[String]("hello") }The standard pattern is to create a singleton object extending RequestVar instead of creating an instance variable of a concrete RequestVar subclass. This is preferred because RequestVar will use the name of its instantiating class for part of its state maintenance mechanism.
If you find it necessary to create a RequestVar subclass of which there may be more than one instance, it is necessary to override the nameSalt() method to return a unique salt value for each instance to prevent name collisions.