24.5 Creating a new valuator

Constructor function: Marpa_Value marpa_v_new ( Marpa_Tree t )

On success, does the following:

• Creates a new valuator. The parent object of the new valuator will be the tree iterator t.
• Sets the reference count of the new valuator to 1.
• Sets new valuator to active. A valuator is always either active or inactive.
• Increases the reference count of t by 1.
• “Pauses” the parent tree iterator.

As long as a parent tree iterator is paused marpa_t_next() will not succeed, and therefore the parent tree iterator cannot move on to a new parse tree. Many valuators can share the same parent parse tree. A tree iterator is “unpaused” when all of the valuators of that tree iterator are destroyed.

Return value: On success, the newly created valuator. On hard failure, NULL.