From: spinutids@...
Date: 2019-02-16T06:02:29+00:00
Subject: [ruby-core:91574] [Ruby trunk Feature#15606] Precedence of -@ and +@

Issue #15606 has been updated by spinute (Satoru Horie).


Compatibility is essential in Ruby. So, we need strong evidence when we break it.

I do not think the current behavior is weird.

`<something>.abs` returns positive value, consistently.

A programmer who knows `-i.abs` is evaluated as `-(i.abs)` can get an expected result. As a note, `-` in `-1` is not an operator, so `-1.abs == (-1).abs == 1`. `-i.to_s` is also explained in the same way.

I agree that the behavior may be confusing for beginners.

----------------------------------------
Feature #15606: Precedence of -@ and +@
https://bugs.ruby-lang.org/issues/15606#change-76838

* Author: sos4nt (Stefan Sch����ler)
* Status: Feedback
* Priority: Normal
* Assignee: 
* Target version: 
----------------------------------------
`-@` and `+@` seem to have issues with method chaining:

```ruby
i = 5

-i.negative?
# NoMethodError (undefined method `-@' for false:FalseClass)
```

here's another example:

```ruby
# frozen_string_literal: true

+'foo'.upcase!
# FrozenError (can't modify frozen String)
```

I know that I can fix this by adding parentheses, i.e. `(-i).negative?` and `(+'foo').upcase!` but it feels cumbersome.

Shouldn't the above work out of the box?

Unless I'm missing a crucial use case, the precedence for `-@` and `+@` should be changed.



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