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### Re^2: Conditional Operator Confusion

by Melly (Hermit)
 on Nov 29, 2006 at 15:48 UTC ( #586722=note: print w/replies, xml ) Need Help??

in reply to Re: Conditional Operator Confusion

Hey! The camel book told me it was just like an if-else (well, sort of). Hmm, I must admit that I'm still slightly in the dark here - none of the examples given so far help me understand exactly what is going on...

```map{\$a=1-\$_/10;map{\$d=\$a;\$e=\$b=\$_/20-2;map{(\$d,\$e)=(2*\$d*\$e+\$a,\$e**
2-\$d**2+\$b);\$c=\$d**2+\$e**2>4?_:0}1..99;print\$c}0..59;print\$/}0..20;
Tom Melly, pm@tomandlu.co.uk

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Re^3: Conditional Operator Confusion
by Herkum (Parson) on Nov 30, 2006 at 16:44 UTC

The trinary is much like any other operator, for example ==. Lets try this example,

```my \$result = \$a == \$b

Here, you get the result of the == operator, is \$a equal \$b. If they match it returns true, if they don't match it returns false.

The trinary works in a similar manner except you are setting the value returned instead of the implied value of other operators.

```my \$result = \$a == \$b ? 1 : 0;

This does the same thing as the first example, except you are explicitly setting the value returned. Does this help?

Not really... I'm sure I'm being really dumb here, but I still don't understand, in the following example, why \$x gets set to "FALSE"... just very, very confused...

```1==1?\$x='TRUE':\$y='FALSE';
print "x=\$x\n";
Tom Melly, pm@tomandlu.co.uk

The conditional operator has higher precedence than the assignment operator, so
\$c?\$x='TRUE':\$y='FALSE'
is the same as
(\$c?\$x='TRUE':\$y)='FALSE'

The addition operator has higher precedence than the conditional operator, so
\$c?\$x+2:\$y+3
is the same as
\$c?\$x+2:(\$y+3)

If you want to do assignments, use if or add parens. Think of as the conditional operator as an operator that returns something.

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