问题
Is it a good practice to use the ternary operator for this:
answersCounter = answer.length != 0 ? ++answersCounter : answersCounter;This is a question that I always asked myself as it happens quite often. Or is it better to use a normal if statement. For me this looks much cleaner in one line.
回答1:
This is just opinion, but I think that writing the increment like you have it is somewhat poor style.
Assigning a variable to a pre-incremented version of itself is a little bit confusing. To me, the best code is the clearest (excepting nods to optimization where necessary), and sometimes brevity leads to clarity and sometimes it does not (see anything written in Perl... I kid, sorta).
Have you ever had the programming trick question of:
int i = 5;
i += i++ + i;
Or something similar? And you think to yourself who would ever need to know how that works out since when would you ever assign a variable to the pre/post increment version of itself? I mean, you would never ever see that in real code, right?
Well, you just provided an example. And while it is parseable, it is not idiomatic and not clearer than a straight forward if.
E.g.
if (answer.length != 0) answersCounter++;
Of course, some people don't like if statements with out braces, and don't like braces without newlines, which is probably how you ended up with the ternary. Something with the coding style needs to be re-evaluated though if it is resulting in (subjectively) worse code to avoid a few carriage returns.
Again, this is opinion only, and certainly not a rule.
回答2:
For Javascript
As it's unclear whether OP is asking about Java, JavaScript or genuinely both.
Also know this is an old question but I've been playing with this and ended up here so thought it worth sharing.
The following does nothing, as incrementers within ternary operators don't work as expected.
let i = 0;
const test = true;
i = test ? i++ : i--;
console.log(i) // 0
Switching ++ to +1 and -- to -1 does work.
However it conceptually is a little strange. We are creating an increment of the variable, then assigning that incremented variable back to the original. Rather than incrementing the variable directly.
let i = 0;
const test = true;
i = test ? i+1 : i-1;
console.log(i) // 1
You can also use the logical operators && and ||.
However I personally find this harder to read and know for sure what will be output without testing it.
let i = 0;
const test = true;
i = test && i+1 || i-1;
console.log(i) // 1
But at the end of the day as commented above, an if else statement seems to be the clearest representation.
This increments the variable directly, and if brevity is the aim then it can still all go on one line.
let i = 0;
const test = true;
if (test) { i++ } else { i-- }
console.log(i) // 1
来源：https://stackoverflow.com/questions/37800489/ternary-operator-use-to-increase-variable