JavaScript SyntaxError - Unexpected string
The occurrence of a “SyntaxError: Unexpected string” in JavaScript happens when a programmer uses string data type in an expression, statement, or declaration where it is not appropriate, this syntax error stops the script and it may happen due to incorrect placement of strings in expressions, variables, etc, let's get to know this error better through its causes and examples on how to solve it.
Understanding an error
If you're seeing this error, it means that there's something wrong with a string in your code, JavaScript is pretty particular about how strings are used and where they're placed, if you put a string right after another string or identifier without using the right operator or separator, it breaks the language's rules and you'll end up with a SyntaxError, so make sure your strings are formatted correctly and in the right spot.
Message:
SyntaxError: Unexpected string
Error Type:
SyntaxError
Case 1: Concatenation Without an Operator
Error Cause:
String concatenation in JavaScript requires the +
operator to combine strings. If strings are placed next to each other without this operator, an "Unexpected string" error occurs.
Example:
let greeting = "Hello" "World";
console.log(greeting);
Output:
SyntaxError: Unexpected string
Resolution of error
To resolve this error, use the + operator to concatenate the strings.
let greeting = "Hello" + " World";
console.log(greeting);
Output
Hello World
Case 2: String Used in Place of an Identifier
Error Cause:
If a string is mistakenly placed where an identifier is expected, such as variable names or function names, an "Unexpected string" error occurs.
Example:
let "name" = "GeeksForGeeks";
console.log("name");
Output:
SyntaxError: Unexpected string
Resolution of error
Ensure that the string is used correctly, either as a string literal or as a properly named identifier.
let name = "GeeksForGeeks";
console.log(name);
Output
GeeksForGeeks
Case 3: Unclosed Strings
Error Cause:
An unclosed string, where the ending quote is missing, results in an "Unexpected string" error.
Example:
let message = "Hello, World;
console.log(message);
Output:
SyntaxError: Unexpected string
Resolution of error
To escape this sort of confusion, make sure that the string is wrapped in double quotes.
let message = "Hello, World";
console.log(message);
Output
Hello, World
Conclusion
To avoid "Unexpected string" errors in JavaScript, ensure that strings are correctly formatted and used appropriately in the code. Strings should be properly closed with matching quotes, and when concatenating strings, the +
operator should be used. Correct placement and usage of strings within expressions and identifiers are crucial to maintain code integrity and functionality.