Ternary Operator? (?:)

[CodexArcanum]

I may just be missing it, but I don't think Cobra has a ternary operator or a construct to replace it. It's a pretty common idiom in C#, and Python recently added one as well.

The C# version might go like:

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var example = a < b ? ValueC : ValueD

The python one is similar in function but formatted different:

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var example = ValueC if a < b else ValueD

That one kind of implies that ValueC is the default and ValueD is a backup.

Cobra may already do something like that, but I haven't seen it. I know you can do a two-line if-else using commas, like:

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if a < b, example = ValueC
else, example = ValueD

(Oddly enough, you don't even have to declare example first. It appears to "leak" out of the if-else scope and be available afterwards).
But I think the one-liner isn't possible.

Would that be a worthwhile addition to the language, and if so which format to go with?

[Charles]

We have it now:

plural = if(items.count==1, '', 's')
name = if(customer, customer.name, '(noname)')   # assuming customer's type is Customer?

# the general form is:
if(CONDITION, TVALUE, FVALUE)

Only one of TVALUE or FVALUE is evaluated. The type is the greatest common denominator type between TVALUE and FVALUE.

It's called the "if expression". It uses the same keyword as the statement ("if") and it follows the same order (condition, truth part, false part).

See also the barely started reference manual which should really be subsumed into the wiki:

-- http://cobra-language.com/docs/manual/expressions/if.html
-- http://cobra-language.com/docs/manual/

Hmm, methinks that we need a How To on various kinds of expressions.

Regarding the scope of "example", that's correct. Cobra is more like Python and less like C# in the treatment of local variables. I call them "hassle free locals".

[Charles]

Rather than a How To, I think I'll do a wiki page called something like ExpressionTour.

[Gameday]

Looks nice. Gonna make use of it

[CodexArcanum]

Oh! Too cool, that's really helpful. I think I actually ignored that page because I thought it was just discussing the regular "if statement" not a separate "if expression", though now that I see if I do like the syntax. Short and sweet.