javascript - Can the ternary operator be equivalent to short circuiting with the logical operators? -

with short circuiting can prevent evaluation of part of expression:

let x = "", y = 123; x && alert("foo"); // "" y || alert("bar") // 123 

since logical ops form expressions can use them in function invocations or return statements.

but ultimately, that's nothing more conditional branching , can reached ternary operator:

x ? alert("foo") : x; // "" y ? y : alert("bar"); // 123 

this more readable , concise. there reason utilize short circuiting property of logical operators except illustrative term?

it's true (well, true) that

x ? x : y 

is logically equivalent to

x || y 

however, they're not equivalent in terms of happens when code runs. in ? : case, sub-expression x may evaluated twice. in x || y, it's evaluated once. simple variable references, doesn't matter, if x function call, might affect behavior , it'll affect performance.

(the fact 1 of expressions might evaluated twice meant "almost" in first sentence.)