insteresting thing about return results from function arguments

[uncutstone]

Please take a look at following code and its result.

def geta(a)
a<<1<<2<<3<<4
end

def getb(b)
b=[7,8,9,10]
end

a=[]
b=[]
geta(a)
getb(b)
puts a.inspect
puts b.inspect

the result is:

[1, 2, 3, 4]
[]

 

[gabriele renzi]

uncutstone ha scritto:

Please take a look at following code and its result.

def geta(a)
a<<1<<2<<3<<4
end

here you're changing the argument (side effet)

def getb(b)
b=[7,8,9,10]
end

here you're just changing the local variable, thus

a=[]
b=[]
geta(a) # changing the empty array referenced by "a"
getb(b) # leaving the empty array happily alone