Java Single Conditional Operator

[Brian Goetz]

Let’s go back to why we have the ternary expression in the first place.  Contrary to popular belief, it is *not* for syntactic concision.

The difference between

    int x;
    If (b)
        x = a;
    else
        x = b;

and

    Int x = b ? a : b

Is that the latter is a _more constrained_ construct than the former.  In the former, the then/else blocks of the if can contain arbitrary statements, and there is no way (other than DA/DU analysis) to capture the intention that we will assign to x in each arm (or even that there are both arms.)  Whereas the latter is an _expression_, and expressions are _total_.  So the latter makes use of a more constrained mechanism, and therefore allows for richer type-checking.  The concision is merely a bonus.

Your proposal conflates statements and expressions; the ternary conditional is an expression, whose arms are expressions, but you want to use a version of it for statements.  And why?  So you can type *two fewer characters*.  It offers no additional type checking, introduces a gratuitously different way to do the same thing, and creates the Frankenstein monster of an operator that is really a statement.  And it doesn’t result in more readable code; arguably, less readable, since we’re less use to spotting side-effects nestled in what look like expressions.

If you mean “if (condition) do stuff”, then there’s no shame in saying exactly that.


On Aug 23, 2022, at 2:28 PM, sankar singh <sankar.singu at gmail.com<mailto:sankar.singu at gmail.com>> wrote:

Hi Team,

We are using ternary operator

Can we use single conditional code like the below.

if (a>50)
   print("50 more")

a>50?.  print("50 more")


--

regards,

Shankar.S

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