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    <blockquote> <p>Does every if-else constructs can be replaced by an equivalent conditional expression using conditional operator?</p> </blockquote> <p>No, you've asked this backwards. <strong>The "bodies" of if/else contain statements, and it is not possible to turn every statement into an expression</strong>, such as try, while, break statements, as well as declarations. Many "statements" are really expressions in disguise, however:</p> <pre><code>++i; blah = 42; some_method(a,b,c); </code></pre> <p>All of these are statements which consist of one expression (increment, assignment, function-call, respectively) and could be turned into expressions within a conditional.</p> <p>So, let's reverse the question, since it sounds like you really want to know how equivalent if/else statements are to ternary conditional expressions: <strong>Can every conditional expression be replaced by equivalent if/else statements?</strong> Almost all, yes. A common example is return statements:</p> <pre><code>return cond ? t : f; // becomes: if (cond) return t; else return f; </code></pre> <p>But also other expressions:</p> <pre><code>n = (cond ? t : f); // becomes: if (cond) n = t; else n = f; </code></pre> <p>Which starts to point to where conditional expressions cannot be easily replaced: <strong>initializations</strong>. Since you can only initialize an object once, you must break up an initialization that uses a conditional into using an explicit temporary variable instead:</p> <pre><code>T obj (cond ? t : f); // becomes: SomeType temp; if (cond) temp = t; else temp = f; T obj (temp); </code></pre> <p>Notice this is much more tedious/cumbersome, and requires something type-dependent if SomeType cannot be default-constructed and assigned.</p>
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    1. POCan every if-else construct be replaced by an equivalent conditional expression?
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    1. POCan every if-else construct be replaced by an equivalent conditional expression?
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    1. CO"The "bodies" of if/else contain statements, and it is not possible to turn every statement into an expression"--that's clears my all doubt. :)
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      1. USwhacko__Cracko
    2. COAlso, initialization of a const variable cannot be broken up into an if statement: `const T obj = cond ? t : f;` <= cannot change without removing const.
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    3. COCuriously enough, C++0x lets one turn any bunch of statements into an expression using lambdas.
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      1. USPavel Minaev
 

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