The JavaScript exception "missing name after . operator" occurs when there is a problem
with how the dot operator (.) is used
for property access.
Message
SyntaxError: missing name after . operator (Firefox)
SyntaxError: Unexpected token '['. Expected a property name after '.'. (Safari)
Error type
What went wrong?
The dot operator (.) is used for property access.
You will have to specify the name of the property that you want to access.
For computed property access, you might need to change your property access from using a
dot to using square brackets. These will allow you to compute an expression. Maybe you
intended to do concatenation instead? A plus operator (+) is needed in that
case. Please see the examples below.
Examples
Property access
Property accessors
in JavaScript use either the dot (.) or square brackets ([]), but not both.
Square brackets allow computed property access.
const obj = { foo: { bar: "baz", bar2: "baz2" } };
const i = 2;
obj.[foo].[bar]
// SyntaxError: missing name after . operator
obj.foo."bar"+i;
// SyntaxError: missing name after . operator
To fix this code, you need to access the object like this:
obj.foo.bar; // "baz"
// or alternatively
obj["foo"]["bar"]; // "baz"
// computed properties require square brackets
obj.foo["bar" + i]; // "baz2"
// or as template literal
obj.foo[`bar${i}`]; // "baz2"
Property access vs. concatenation
If you are coming from another programming language (like PHP), it is also easy to mix up the dot operator
(.) and the concatenation operator (+).
console.log("Hello" . "world");
// SyntaxError: missing name after . operator
Instead you need to use a plus sign for concatenation:
console.log("Hello" + "World");