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| − | == Motivation ==
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| − | ''Refactoring'' [[Martin Fowler 1999]] states that: "If a method can get a value that is passed in as a parameter by another means, it should."
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| − | == Example ==
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| − | An object invokes a method, then passes the result as a parameter for a method. The receiver can also invoke this method. So the best idea is to remove the parameter and let the receiver invoke the method.
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| − | int basePrice = quantity * itemPrice;
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| − | discountLevel = getDiscountLevel();
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| − | double finalPrice = discountedPrice(basePrice, discountLevel);
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| − | Above we have some code, but lets remove the discountLevel parameter from discountedPrice(basePrice, discountLevel). Now we have:
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| − | int basePrice = quantity * itemPrice;
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| − | double finalPrice = discountedPrice(basePrice);
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| − | The discountedPrice(basePrice) method now looks like:
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| − | discountedPrice(basePrice)
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| − | {
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| − | int discountLevel = getDiscountLevel();
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| − | //does calculation type stuff here
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| − | return discountedPrice;
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| − | }
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