Defining a JavaScript object in console

Question

When I type simple objects to Chrome JavaScript Console, I get an output like this:

>true
true
>1/3
0.3333333333333333

And so on.

Answer 1

Because your statement is being evaluated as a block, not an object literal declaration.

Note that an ExpressionStatement cannot start with an opening curly brace because that might make it ambiguous with a Block. Also, an ExpressionStatement cannot start with the function keyword because that might make it ambiguous with a FunctionDeclaration.

To make it evaluate as an expression, it needs to be the right-hand side of an assignment, wrapped in parentheses or preceded by an operator. (!{a:1,b:2})

Answer 2

 { a: 1, b: 2 }

is a code block, with two wrongly labelled variables.

To create an object, surround the code block by parentheses, so that the braces are interpreted as object literals:

({ a: 1, b: 2 })

Answer 3

Try this instead:

({ "a" : 1, "b" : 2 })

Answer 4

Because your statement is being evaluated as a block, not an object literal declaration.

True josh

If you want it to be evaluated as an object, just write :

> ({a : 1, b : 2})
Object
a: 1
b: 2
__proto__: Object

Answer 5

Because { a: 1, b: 2 } is not a valid expression to execute. JavaScript looks it like a block of code since it starts and ends to curly braces.

If you try ({ a: 1, b: 2 }), it will work.

Answer 6

It's because an opening { with no context is interpreted as the beginning of a block. You can use parentheses:

({ a: 1, b: 2 })

As it is though, it's just a block of execution - like one might find after an if or for. So you can type:

{alert("Hello!");}

Here's more about that. Blocks sort of return values too, which is both awesome and disappointing.