Constructor property of Java Script types

Question

I'm leaning JavaScript and I've read about the constructor property.

I tried

And they all worked. However to my surprise when trying:

They did not, why is that?

Try 123..constructor, the first '.' is a decimal mark. {}.constructor works for me. — Korikulum
– Korikulum, Commented Jun 1, 2014 at 14:33
@Korikulum where? That's a syntax error in the chrome dev tools. It depends on where you're running it. — Benjamin Gruenbaum
– Benjamin Gruenbaum, Commented Jun 1, 2014 at 14:36
Suggest what? You haven't told us what you are trying to do. — JLRishe
– JLRishe, Commented Jun 1, 2014 at 14:36
@BenjaminGruenbaum Yes, you're right, I was doing the following: console.dir({}.constructor);, and that works. — Korikulum
– Korikulum, Commented Jun 1, 2014 at 14:39

Benjamin Gruenbaum · Accepted Answer · 2014-06-01 14:33:15Z

2

This is a parse issue.

When you do 123.constructor the engine experts a decimal after the 123 like 123.123
When you do {}.constructor the engine reads {} as an empty block and then reads . as the first thing in the outer block which is meaningless.

Both of which can be fixed by wrapping these with ()s

(123).constructor; // Number, note this 'boxes'
({}).constructor; // Object

answered Jun 1, 2014 at 14:33

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