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Message
SyntaxError: missing ; before statement
Error type
What went wrong?
There is a semicolon (;
) missing somewhere. JavaScript statements must be terminated with semicolons. Some of them are affected by automatic semicolon insertion (ASI), but in this case you need to provide a semicolon, so that JavaScript can parse the source code correctly.
However, oftentimes, this error is only a consequence of another error, like not escaping strings properly, or using var
wrongly. You might also have too many parenthesis somewhere. Carefully check the syntax when this error is thrown.
Examples
Unescaped strings
This error can occur easily when not escaping strings properly and the JavaScript engine is expecting the end of your string already. For example:
var foo = 'Tom's bar'; // SyntaxError: missing ; before statement
You can use double quotes, or escape the apostrophe:
var foo = "Tom's bar"; var foo = 'Tom\'s bar';
Declaring properties with var
You cannot declare properties of an object or array with a var
declaration.
var obj = {}; var obj.foo = "hi"; // SyntaxError missing ; before statement var array = []; var array[0] = "there"; // SyntaxError missing ; before statement
Instead, omit the var
keyword:
var obj = {}; obj.foo = "hi"; var array = []; array[0] = "there";