除了使用函数外，还有什么方法可以从表达式中引发异常？

Question

Is there a way to explicitly throw an exception from an expression in JavaScript besides placing that throw a function wrapper?

throw is a statement, statements don't produce values, thus they cannot be used in expressions which operate on values and always produce a value. It's quite obvious that any statement can be put to a function and a function call can be used from the expression. Is there a way to avoid wrapping the throw statement to a function and throw from the expression directly?

UPDATE:

Some people say it's not quite clear what I am asking about. Consider a hypothetical example (not for real), this is something I wish worked, but it doesn't:

var one = value != null ? value * value : (throw new Error('The value has not been provided'));

var two = value != 0 ? 1 / value : (throw new Error('The result cannot be evaluated because the value is zero which would give a division by zero problem.));

Answer 1

No. As you say, throw is a statement and statements cannot appear as parts of an expression.

The only way to execute a statement from the evaluation of an expression are a function call or eval . Using a THROW(new Error(…)) function is probably the best you can get.

But seriosly, go with simple, readable statements:

if (value == null) throw new Error('The value has not been provided');
var one = value * value;

if (value == 0) throw new Error('division by zero");
var two = 1 / value;

That will not only work, but also fit in a line.

Answer 2

Yes you can throw from a ternary! Perhaps some might call my solution a bit of a hack, but it is very simple to reason about.

throw from a ternary

var two = value != 0 ? 1 / value : (void 0).throwDivideByZero()