Add simple docs example for struct Cell

[xliiv]

No description provided.

[rust-highfive]

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[BurntSushi]

I don't think this follows the prevailing style in the docs. For example, I think it is at least missing an Examples header. I'd also like to see some prose describing what the example is trying to show.

cc @steveklabnik

[xliiv]

I've added some prose and example section.
BTW: I'd see reference to this blog post:
https://ricardomartins.cc/2016/06/08/interior-mutability
in the docs. but perhaps adding links to blog post is not the way of doing docs. :)

Maybe it's just me but I was reading this https://doc.rust-lang.org/std/cell/ a few times and still didn't know what Cell is all about then read the blog post once to get the concept easily.. .

[steveklabnik]

A few nits, and the build is failing.

[steveklabnik]

A few nits, and the build is failing.

[steveklabnik]

this should be Examples even though there's only one, for consistency

[steveklabnik]

mutable, not muttable

[steveklabnik]

single quotes here please!

[xliiv]

@steveklabnik done

[steveklabnik]

sorry! just some last-minute white space changes; I must have missed them before?

This is good to go once that's fixed; I want to make sure this is consistent with the rest of the standard library.

[steveklabnik]

sorry! just some last-minute white space changes; I must have missed them before?

This is good to go once that's fixed; I want to make sure this is consistent with the rest of the standard library.

[steveklabnik]

can you put a /// above and below this line

[xliiv]

like here? 8286075

Because i put it at first place and it was the cause of CI failure (something related to tidy check)

[steveklabnik]

yes. you had trailing whitespace; that was the only issue, not the ///s. In other words

"///"

not

"/// "

make sense?

[steveklabnik]

also above this line

[steveklabnik]

also one above this line

[steveklabnik]

also one above this line

[steveklabnik]

main isn't the issue. here's the error

01:00:45] 	error[E0425]: cannot find value `immutable` in this scope

[01:00:45]   --> <anon>:22:1

[01:00:45]    |

[01:00:45] 22 | immutable.special_field.set(new_value);

[01:00:45]    | ^^^^^^^^^ not found in this scope

[01:00:45] 

[01:00:45] error[E0425]: cannot find value `immutable` in this scope

[01:00:45]   --> <anon>:23:12

[01:00:45]    |

[01:00:45] 23 | assert_eq!(immutable.special_field.get(), new_value);

[01:00:45]    |            ^^^^^^^^^ not found in this scope

[01:00:45] 

on this line, you use something called "immutable" but you never defined it; it's called my_struct above

[xliiv]

You're right.. maybe i should go to sleep for today :)

[xliiv]

r? @steveklabnik is it ok, what do you think?

[carols10cents]

friendly ping for review @steveklabnik !

[carols10cents]

r? @steveklabnik

[steveklabnik]

@bors: r+ rollup

@xliiv thanks a ton! Sorry for the delays again ☹️

[bors]

📌 Commit d429a4e has been approved by steveklabnik

[xliiv]

@steveklabnik you are welcome :)
I didn't know that contributing to rust is so easy (at least contributing to docs)