From: Paul Brannan <pbrannan@...>
Date: 2001-11-13T00:43:30+09:00
Subject: [ruby-talk:24940] Re: Naming conventions

On Tue, 13 Nov 2001, Hachenberger Peter wrote:

> That's quite an interesting way to solve the problem, but i am curios about
> the definition of the method Complex. As far as I have read, the naming
> convention for methods tells us to begin a method name with a lowercase
> Character. What happens here? Why does ruby know, that Complex is a method
> call here and not the class name?

A = 1                   #=> 1
def A(*x); x; end       #=> nil
A(1)                    #=> [1]
A 1                     #=> [1]
A 1, 2, 3               #=> [1, 2, 3]
A(1, 2, 3)              #=> [1, 2, 3]
A                       #=> 1
A()                     #=> []

Looks like Ruby is treating the identifier just like any other: if it is
by itself, then it tries to look it up as a variable first.  If it is not
by itself (with parens or arugments following), it is treated as a method
call.  This is evident in the following error messages:

irb(main):001:0> foo
NameError: undefined local variable or method `foo' for #<Object:0x40295c90>
        from (irb):1
irb(main):002:0> foo()
NameError: undefined method `foo' for #<Object:0x40295c90>
        from (irb):2

As far as whether it is a good idea to have a method and a constant with
the same name, imo this probably isn't a good idea.  However, naming a
method with a capital letter is commonly used to indicate that the method
is a factory for some particular type (DelegateClass() is a factory for
delegate classes, for example).

Paul