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5.38.Boolean Functions
5.38.1.Boolean Functions
5.38.2.Use strings as arguments of boolean() function.
5.38.3.compares "0" as a string and as a number
5.38.4.uses node-sets as arguments for boolean() function
5.38.5.The not function returns true if its argument is false, and false otherwise.
5.38.6.Functions true() and false() are useful, when some conditions are tested during programming