What is the test for a demurrer on the ground that a pleading does not state facts sufficient to constitute a cause of action?

The rules relating to the trial court's determination of a demurrer on the ground that a pleading does not state facts sufficient to constitute a cause of action and which govern a reviewing court in considering an appeal from a judgment entered on the sustaining of a demurrer on that ground are in [208 Cal.App.2d 278] general as follows: the allegations of the complait must be regarded as true. It is assumed that plaintiff can prove all the fact as alleged; defects in the pleading which do not affect the substantial rights of the parties are disregarded; pleadings must be reasonably interpreted; they must be read as a whole and each part must be given the meaning that it derives from the context wherein it appears; the allegations must be liberally construed with a view to substantial justice between the parties and that the administrtion of justice shall not be embarrassed by technicalities or useless forms. (Hill v. City of Santa Barbara, 196 Cal.App.2d 580, 585 [16 Cal.Rptr. 686].)