Ternary conditionals

[armsys]

Referring to

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::$r = ("a" == "a"); $r = ($r?"True":"False"); msg $r;

,
how to interpret ($r?"true":"False")?
Is the "?" (question mark) an implied "if"?

[highend]

It's a ternary conditional.

Advanced Topcis - Scripting - Ternary Conditionals

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$r = ("a" == "a");

$r = 1

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$r = ($r?"True":"False");

Because $r = 1 (which is also a boolean "true") -> $r = "True"

It's just a short form of an if / else statement.

[armsys]

It's a ternary conditional.

Yes, I found it in the manual. I should have read ahead to locate the description on the weird construct (condition)? value-if-true : value-if-false.
Thank you for your fast help.

[bdeshi]

in my opinion, it's a good idea to enclose the whole thing in another set of braces: ( (condition) ? ReturnIfTrue : ReturnIfFalse )

[armsys]

in my opinion, it's a good idea to enclose the whole thing in another set of braces: ( (condition) ? ReturnIfTrue : ReturnIfFalse )

Thank you for your reminder. Agree. I'll follow your scripting style because it helps improve readability.

[autocart]

1) is it safe to use expressions in the if-true and if-false parts of the ternary conditional?
2) is it safe to nest ternary conditionals? e.g.: $coolVar = $groofyVar?groofyVar:isset($coolVar)?$coolVar:""; $coolVar = $groovyVar?groovyVar:isset($coolVar)?$coolVar:"";

[admin]

I'd think so. But the parsing can get tricky depending on what you do. Make a test...

ADD:
Parentheses help. This seems to work. Play with it...

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// nested ternaries
  //$coolVar = "cool";
  //$groofyVar = "groof";
  echo (isset($groofyVar)?$groofyVar:(isset($coolVar)?$coolVar:"NO"));

[bdeshi]

It's perfectly okay to nest ternary conditionals or expressions within another ternary. You can also have ternaries in expressions. As I commented earlier here, when in doubt, enclose in braces.

[autocart]

just realized that groovy is spelled with a "v". (I think I was connecting it to goofy in my mind at first.)
sorry for misleading u, Don, I am also not a native English speaker.

Thx for all help.

[admin]

Luckily I coded it so that mispelled variables also work!