It is not only the verbosity or use of trailing '!' in a method
for no real reason, IMO, but also things such as "1.month". I
understand that rails thrives as a DSL, but to me having a method
such as .month on an Integer, is simply wrong. Same with
HashWithIndifferentAccess - I understand the point, to not have
to care whether a key is a String or a Symbol, but it is simply
the wrong way to think about this. People who use HashWithIndifferentAccess
do not understand Symbols.
The exclamation mark has a reason: if the newly created records fails validations, an exception is raised. Without the exclamation mark, the error is silenced (and the method returns a falsey value). This is a convention across Rails.
Ruby itself mostly uses it for mutating methods (e.g. #gsub("a", "b") replaces the character a with b in a string and returns a new string, but #gsub!("a", "b") mutates the original.
> I understand that rails thrives as a DSL, but to me having a method such as .month on an Integer, is simply wrong
It's not that different from `1.times` or `90.chr` which are vanilla Ruby.
> HashWithIndifferentAccess
HashWithIndifferentAccess was an unfortunate necessity to avoid DOS attacks when Symbols used to be immortal. There's no longer a reason to use it today, except for backward compatibility.
`1 + 1` in Ruby is syntactic sugar for `1.+(1)`. Nothing wrong about it at all, it's just different from what you're apparently used to. This type of thing isn't even unique to Ruby or even OOP.
This is a typical API design in Ruby, but the post is about a somewhat novel API design than what you're pointing out. To address some of your points:
The exclamation mark is a convention. It is used whenever a method could possibly result in an exception being raised. Sometimes it's instead used for non-idempotent methods.
"3.days", etc are Rails things. A lot of non-Rubyists don't like it but once you use it for long enough you tend to really grow to it.
As for HashWithIndifferentAccess, yes this is generally acknowledged as a mistake in Ruby's design and is rarely used in my experience. Originally, all Ruby hashes were HWIA. When they finally realized this was a design mistake they had to create HWIA for some level of backwards compatibility
