Editing Ternary conditional operator (section)

==?: in style guidelines==
Conditional operators are widely used and can be useful in certain circumstances to avoid the use of an {{code|if}} statement, either because the extra verbiage would be too lengthy or because the syntactic context does not permit a statement. For example:

 [[C preprocessor|#define]] MAX(a, b) (((a)>(b)) ? (a) : (b))

or

<syntaxhighlight lang="cpp">
 for (i = 0; i < MAX_PATTERNS; i++)
    c_patterns[i].ShowWindow(m_data.fOn[i] ? SW_SHOW : SW_HIDE);
</syntaxhighlight>

(The latter example uses the [[Microsoft Foundation Classes]] Framework for [[Win32]].)

===Initialization===
An important use of the conditional operator is in allowing a single initialization statement, rather than multiple initialization statements. In many cases this also allows [[single assignment]] and for an identifier to be a [[constant (computer programming)|constant]].

The simplest benefit is avoiding duplicating the variable name, as in Python:

<syntaxhighlight lang="python">
x = 'foo' if b else 'bar'
</syntaxhighlight>

instead of:

<syntaxhighlight lang="python">
if b:
    x = 'foo'
else:
    x = 'bar'
</syntaxhighlight>

More importantly, in languages with [[block scope]], such as C++, the blocks of an if/else statement create new scopes, and thus variables must be declared ''before'' the if/else statement, as:

<syntaxhighlight lang="cpp">
std::string s;
if (b)
    s = "foo";
else
    s = "bar";
</syntaxhighlight>

Use of the conditional operator simplifies this:

<syntaxhighlight lang="cpp">
std::string s = b ? "foo" : "bar";
</syntaxhighlight>

Furthermore, since initialization is now part of the declaration, rather than a separate statement, the identifier can be a constant (formally, of [[const (computer programming)|{{code|const}}]] type):

<syntaxhighlight lang="cpp">
const std::string s = b ? "foo" : "bar";
</syntaxhighlight>

===Case selectors===
When properly formatted, the conditional operator can be used to write simple and coherent case selectors. For example:

<syntaxhighlight lang="c">
vehicle = arg == 'B' ? bus :
          arg == 'A' ? airplane :
          arg == 'T' ? train :
          arg == 'C' ? car :
          arg == 'H' ? horse :
                       feet;
</syntaxhighlight>

Appropriate use of the conditional operator in a variable assignment context reduces the probability of a bug from a faulty assignment as the assigned variable is stated just once as opposed to multiple times.