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    <p>There is no reason why that reference would be wrong or bad. If what you want is a local short-cut name ("alias"), references are <em>the</em> way to go. If you copy the float into a new variable, then you will get a new object and as you pointed out, of course you will also get a new address: Not at all what you would have wanted. So take a reference for that:</p> <pre><code>float &amp;x = some.buried.variable.elsewhere; </code></pre> <p>Which will behave as the original variable in expressions. </p> <p>However, as with everything, hard-coded rules won't do it. It depends on the specific situation. If you don't care about the <em>object</em>, but rather about the object's <em>value</em>, then create a copy. It's better to use the float directly than have that possible indirection through a reference when all you are interested in is to get easy access to the <em>value</em> of something. </p> <p>What is bad is to use a reference when storing the result of a computation - because what is clearly of interest is the value only. You couldn't have any interest in a temporary float identity anyway, because it doesn't exist in the first place: A temporary float is not an object. It isn't even required to have any address (which can happen if the compiler keeps the float in a register):</p> <pre><code>float const &amp;x = 3.0; // non-sense. don't use reference here </code></pre> <p>Same with the result of a function call of course</p> <pre><code>float const &amp;x = get_some_float(); // non-sense too. </code></pre>
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    1. POconst float & x = something; // considered harmful?
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    1. USJohannes Schaub - litb
    1. USJohannes Schaub - litb
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    1. COIt seems that last bit isn't quite right for the case of const references - see Vincent's reply and link to Herb Sutter...
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    2. COthat trick he is refering to is to avoid a virtual destructor when using a polymorphic class. It doesn't have any sense in cases where you have some type T, and you bind it to a T const&. you won't have any polymorphic behavior (and the copy constructor must still be visible for both cases anyway)
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      1. USJohannes Schaub - litb
    3. COsee this answer for how to use it: http://stackoverflow.com/questions/455518/how-many-and-which-are-the-uses-of-const-in-c/455535#455535
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