# Description
Closes: #8108
Adding a new `-b` flag to `rename` command. I have thought about making
it as a positional argument, but I don't think it's ok because we alredy
have `...rest` parameters
Here are how they works:
```
# Rename fields based on a given closure
> {a: 1, b: 2} | rename -b {str upcase}
╭───┬───╮
│ A │ 1 │
│ B │ 2 │
╰───┴───╯
# Rename fields based on fields' value
> {a: abc, b: def} | rename -b {|it| $it.value | str upcase}
╭─────┬─────╮
│ ABC │ abc │
│ DEF │ def │
╰─────┴─────╯
```
# User-Facing Changes
# Tests + Formatting
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