SyntaxError: missing ) after condition
En esta página
The JavaScript exception "missing ) after condition" occurs when there is an error with
how an
if
condition is written. It must appear in parenthesis after the if keyword.
Message#
SyntaxError: missing ) after condition (Firefox)
SyntaxError: Unexpected token '{'. Expected ')' to end an 'if' condition. (Safari)
Error type#
{{jsxref("SyntaxError")}}
What went wrong?#
There is an error with how an
if
condition is written. In any programming language, code needs to make decisions and
carry out actions accordingly depending on different inputs. The if statement executes a
statement if a specified condition is truthy. In JavaScript, this condition must appear
in parenthesis after the if keyword, like this:
if (condition) {
// do something if the condition is true
}
Examples#
Missing parenthesis#
It might just be an oversight, carefully check all you parenthesis in your code.
```js-nolint example-bad if (Math.PI < 3 { console.log("wait what?"); }
// SyntaxError: missing ) after condition
To fix this code, you would need to add a parenthesis that closes the condition.
```js example-good
if (Math.PI < 3) {
console.log("wait what?");
}
Misused is keyword#
If you are coming from another programming language, it is also easy to add keywords that don't mean the same or have no meaning at all in JavaScript.
```js-nolint example-bad if (done is true) { console.log("we are done!"); }
// SyntaxError: missing ) after condition
Instead you need to use a correct [comparison operator](/en-US/docs/Web/JavaScript/Reference/Operators).
For example:
```js
if (done === true) {
console.log("we are done!");
}
Or even better:
js example-good
if (done) {
console.log("we are done!");
}