method conditional option pattern

When I have this pattern

sign_me(@user, :event => :authentication, :subdomain => subdomain)

how can I write it to avoid sending the :subdomain option if subdomain.nil? ( if possible …)

sign_me(@user, :event => :authentication #?, :subdomain => subdomain unless subdomain.nil? )

When I have this pattern

       sign_me(@user, :event => :authentication, :subdomain => subdomain)

how can I write it to avoid sending the :subdomain option if
subdomain.nil? ( if possible ..)

       sign_me(@user, :event => :authentication #?, :subdomain =>
subdomain unless subdomain.nil? )

I'm not sure if it's possible to do it in a single line (as far as you want
to have a tidy code)

opts = { event: :authentication }
opts[:subdomain] = subdomain if subdomain

sign_me @user, opts

thanks

When I have this pattern

       sign_me(@user, :event => :authentication, :subdomain => subdomain)

how can I write it to avoid sending the :subdomain option if subdomain.nil?
( if possible ..)

       sign_me(@user, :event => :authentication #?, :subdomain => subdomain
unless subdomain.nil? )

You could try
        sign_me(@user, :event => :authentication, (:subdomain =>
subdomain unless subdomain.nil?) )
or
        sign_me(@user, :event => :authentication, :subdomain =>
(subdomain unless subdomain.nil?) )

Colin

> When I have this pattern
>
> sign_me(@user, :event => :authentication, :subdomain => subdomain)
>
> how can I write it to avoid sending the :subdomain option if
subdomain.nil?
> ( if possible ..)
>
> sign_me(@user, :event => :authentication #?, :subdomain =>
subdomain
> unless subdomain.nil? )

You could try
        sign_me(@user, :event => :authentication, (:subdomain =>
subdomain unless subdomain.nil?) )

I was surprised that you answered this Colin so I tried it out but I got a
syntax error

app.root_path(foo: 'me', (bar: 'blah' if false))

SyntaxError: (irb):17: syntax error, unexpected tLABEL
app.root_path(foo: 'me', (bar: 'blah' if false))
                              ^
(irb):17: syntax error, unexpected ')', expecting tASSOC
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands/console.rb:47:in
`start'
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands/console.rb:8:in
`start'
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands.rb:41:in
`<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'

or
        sign_me(@user, :event => :authentication, :subdomain =>
(subdomain unless subdomain.nil?) )

and this still passes subdomain as a key if used in a hash but if used in a
routes helper, this will work :smiley:

app.root_path(foo: 'me', bar: ('blah' if false))

=> "/?foo=me"

> When I have this pattern
>
> sign_me(@user, :event => :authentication, :subdomain =>
> subdomain)
>
> how can I write it to avoid sending the :subdomain option if
> subdomain.nil?
> ( if possible ..)
>
> sign_me(@user, :event => :authentication #?, :subdomain =>
> subdomain
> unless subdomain.nil? )

You could try
        sign_me(@user, :event => :authentication, (:subdomain =>
subdomain unless subdomain.nil?) )

I was surprised that you answered this Colin so I tried it out but I got a
syntax error

app.root_path(foo: 'me', (bar: 'blah' if false))

SyntaxError: (irb):17: syntax error, unexpected tLABEL
app.root_path(foo: 'me', (bar: 'blah' if false))
                              ^
(irb):17: syntax error, unexpected ')', expecting tASSOC
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands/console.rb:47:in
`start'
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands/console.rb:8:in
`start'
from
/home/jim/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.2.2/lib/rails/commands.rb:41:in
`<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'

I am not surprised that did not work, my answer was not intended to
convey any suggestion that it would work, just something that would be
interesting to try.

or
        sign_me(@user, :event => :authentication, :subdomain =>
(subdomain unless subdomain.nil?) )

and this still passes subdomain as a key if used in a hash but if used in a
routes helper, this will work :smiley:

Yes, it will pass the subdomain as nil, so it depends on the context
whether this is satisfactory.

Colin

I have a related question.
I was suggesting Erwin to use just:

sign_me(@user, :event => :authentication #?, :subdomain => subdomain)

because if subdomain is nil, sign_me should correctly handle it.
I mean, in an hypothetical sign_in method I'd write:

def sign_me(user, options)
   if options[:subdomain]
     # do_something
   end
end

if subdomain is nil the method handles it correctly.
but with this code:

def sign_me(user, options)
   if options.has_key? :subdomain
     # do_something
   end
end

this goes wrong ("options.has_key? :subdomain" is true)! So I'd say the first implementation seems more correct, do you agree with me or I' missing something important about checking hash parameters?

I have a related question.
I was suggesting Erwin to use just:

sign_me(@user, :event => :authentication #?, :subdomain => subdomain)

because if subdomain is nil, sign_me should correctly handle it.
I mean, in an hypothetical sign_in method I'd write:

def sign_me(user, options)
  if options[:subdomain]
    # do_something
  end
end

if subdomain is nil the method handles it correctly.

That is the way I would do it.

Colin

Thanks Colin

I finally decided to keep the :subdomain option and let the method decide about what to do with it ( seems to be the common pattern)