Page 155 of the Camel book distinguishes between an undefined string and a null one. St. Larry writes: "Many operations return the undefined value under exceptional conditions, such as the end of file, uninitialized variable, system error, and such. This defined function allows you to distinguish between an undefined null string and a defined null string when you're using operators that might return a real null string."

In reply to Re: Baby Steps by Anonymous Monk
in thread Baby Steps "if" behavior? by PipTigger

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