Issues with "Description" and "Hoisting" in var documentation.

[domleonard]

MDN URL

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/var

What specific section or headline is this issue about?

Description and Hoisting sections

What information was incorrect, unhelpful, or incomplete?

1. The Description section states

The scope of a variable declared with var is one of the following curly-brace-enclosed syntaxes that most closely contains the var statement:

• Function body
• Static initialization block

Or the current module or script, if it's contained in neither of these.)

The issue: Scripts that are not modules don't create their own variable scope;

2. The Hoisting section states in the second sentence

Declaring a variable anywhere in the code is equivalent to declaring it at the top.

The issue The "top" of what is not defined and could benefit from including a "top of the containing script" option.

What did you expect to see?

under Description

Or the current module or script, if it's contained in neither of these.

might benefit from being reworded along the lines of:

Or if it's not contained in either of these,

• the module a var is declared within, or
• global scope if the declaration is not within a module.

Second sentence of Hoisting

Declaring a variable anywhere in the code is equivalent to declaring it at the top.

might benefit from being reworded along the lines of:

Declaring a variable anywhere in the code is equivalent to declaring it at the top of the function, static initialization block or script it is declared in.

Do you have any supporting links, references, or citations?

No response

Do you have anything more you want to share?

The reason for suggestions in this request comes from this Stack Overflow question about why a global variable in a script is not hoisted such that it can be accessed in a preceding script without generating a run time error.

The obvious answer about a timing error - the second script tag had not been encountered or processed at the time the first script was executed - doesn't appear to be covered in question answers, the nominated duplicate question on Stack Overflow, or in MDN articles for var (this amendment request) or the glossary definition for Hoisting.

MDN metadata

Page report details

• Folder: en-us/web/javascript/reference/statements/var
• MDN URL: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/var
• GitHub URL: https://github.com/mdn/content/blob/main/files/en-us/web/javascript/reference/statements/var/index.md
• Last commit: 1c4869c
• Document last modified: 2023-07-03T17:55:26.000Z

[Josh-Cena]

You are totally right—interaction of multiple scripts is very tricky and it's not documented here, because it's not JS semantics but HTML semantics. Still it's worth mentioning.

Do you want to submit a PR? I can review.