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Ruby
1

Hi,

I’m quite new to Ruby, so please excuse me if this question is a bit
silly.

Consider:

class Foo
def initialize
@a = []
end

def bar§
@a << p
end
end

It’s nice that Ruby returns the last evaluated expression, without
putting an explicit return. However, Foo#bar dangerously exposes the
Foo class internals.

My question is, what is the common idiom to avoid this? Simply adding
a return nil? def bar§; @a << p; return nil; end

Thanks in advance

2

2007/11/9, [email protected] [email protected]:

end
My question is, what is the common idiom to avoid this? Simply adding
a return nil? def bar(p); @a << p; return nil; end

In this case I’d do

def bar(x)
@a << x
self
end

Because then you can nicely chain calls to #bar. Depending on
circumstances you might even consider implementing #<< instead of /
additionally to #bar.

Kind regards

robert

3

On Nov 9, 2007, at 09:41 , Robert K. wrote:

2007/11/9, [email protected]
[email protected]:

a return nil? def bar(p); @a << p; return nil; end

In this case I’d do

def bar(x)
@a << x
self
end

Follow this advice.

use.inject do |as, often| as.you_can - without end

Ignore this advice.

4

Ok, thanks a lot for the tips.