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ViewsTypeError: console.log(...) is not a function
I'm really confused how I can get console.log is not a function on line 1091. If I remove the closure below, line 1091 doesn't complain such error. Chrome Version 43.0.2357.130 (64-bit).
Here is the code:
$scope.columnNameChanged = function (tableColumn) {
setDirtyColumn(tableColumn);
//propagate changes to the key fields
for (var i = 0; i < $scope.tableIndexes.length; ++i) {
for (var j = 0; j < $scope.tableIndexes[i].columnName.length; ++j) {
if ($scope.tableIndexes[i].columnName[j] === tableColumn.previousName) {
console.log('xxx', $scope.tableIndexes[i].columnName[j])
(function (i, j) {
$timeout(function () {
console.log($scope.tableIndexes[i].columnName[j])
$scope.tableIndexes[i].columnName[j] = tableColumn.name.toUpperCase();
console.log($scope.tableIndexes[i].columnName[j])
});
})(i, j);
}
}
}
};
3 answers
Answer question0
Solution
Simply put a semicolon (;) after console.log(…).
Explanation
The error is easily reproducible like this:
console.log()
(function(){})It’s trying to pass function(){} as an argument to the return value of console.log() which itself is not a function but actually undefined (check typeof console.log();). This is because JavaScript interprets this as console.log()(function(){}). console.log however is a function.
If you didn’t have the console object you’d see
ReferenceError: console is not defined
If you had the console object but not the log method you’d see
TypeError: console.log is not a function
What you have, however, is
TypeError: console.log(...) is not a function
Note the (...) after the function name. With those it’s referring to the return value of the function.
The line break doesn’t separate these two expressions as separate statements because of JavaScript’s rules for automatic semicolon insertion (ASI).
Respect the ;
All these code snippets result in all sorts of unexpected errors if no semicolons are present:
console.log() // As covered before
() // TypeError: console.log(...) is not a function
console.log() // Accessing property 0 of property 1 of the return value…
[1][0] // TypeError: console.log(...) is undefined
console.log() // Like undefined-3
-3 // NaN
let a, b;
const array = Array.from({ length: 2 })
// Now, let’s use destructuring:
[a, b] = array; // ReferenceError: can't access lexical declaration 'array' before initialization
let a, b;
const array = Array.from({ length: 2 }).fill(1),
array2 = Array.from({ length: 2 })
// Now, let’s use destructuring. Attempt to get the two 1’s from `array` as `a` and `b`:
[a, b] = array;
console.log(a, b); // undefined undefined
Another Example
You see the (...) oftentimes with the use of chained methods or chained property accessors:
string.match(/someRegEx/)[0]
If that RegEx isn’t found, the method will return null and the property accessor on null will cause a TypeError: string.match(...) is null — the return value is null. In the case of console.log(...) the return value was undefined.
0
The error means that the return value of console.log() is not a function. You are missing a semicolon:
console.log('xxx', $scope.tableIndexes[i].columnName[j]);
// ^
which makes the following (...) of the IIFE to be interpreted as a function call.
Compare the error messages of
> var foo = {bar: undefined};
> foo.bar();
Uncaught TypeError: foo.bar is not a function
and
> var foo = {bar: function(){}};
> foo.bar()();
Uncaught TypeError: foo.bar(...) is not a function
0
2020 Update
One possible cause can be the declaration of var console somewhere in your script.
Use:
window.console.log(...);
instead. Worked for me.
I hope it helps