inconsistent naming: `Array::length` and `Array::rev`

[lijunchen]

The current API design of the Array type is inconsistent in its method naming conventions. It provides both a length and a rev method. For better consistency and clarity, the naming should be standardized to use either:

• len and rev - following a shorter, more succinct naming convention.
• length and reverse - using more descriptive, complete names.

[qazxcdswe123]

As well as Map.size(), which is neither len nor length

[bobzhang]

@qazxcdswe123 shall we all call it len and deprecate the old API?

[glyh]

I second len, but I think as long as the naming is consistent, it wouldn't matter too much.

[qazxcdswe123]

@qazxcdswe123 shall we all call it len and deprecate the old API?

According to grep, most of the current API use length so maybe just stick with length?

---

And we also have lots of size

[lijunchen]

also need to consider rev_each, rev_eachi etc.

[peter-jerry-ye]

Update: we now decide to

• unify to len (for length and size), aligning with Rust, and
• keep length for the time being and deprecate size as size has fewer occurences (only for map and set). We will provide migration tool for length in the future