Lazy Evaluation and "undefined" I am on the road to being a haskell programmer, and it still is a long way to go. Yesterday I had some nice guys from #haskell explain to me lazy evaluation. Take a look at this code: Prelude> let x = undefined in "hello world" "hello world" Prelude> Because of Haskells lazyness, x will not be evaluated because it is not used, hence undefined will not be evaluated and no exception will occur. The evaluation of "undefined" will result in a runtime exception: Prelude> undefined *** Exception: Prelude.undefined Prelude> Strictness Strictness means that the result of a function is undefined, if one of the arguments, the function is applied to, is undefined. Classical programming languages are strict. The following example in Java will demonstrate this. When the programm is run, it will throw a RuntimeException, although the variable "evilX" is never actually used, strictness requires that all argu
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