Ok..but why always uses VAL in examples?

# announcements

[Leandro Cavalheiro]

Ok..but why always uses VAL in examples?

[karelpeeters]

If you don't need a variable to be mutable it's a good idea to make it immutable because you avoid a bunch of possible bugs that way.

[karelpeeters]

It also expresses your intent more clearly, when you declare the variable you immediately say that it will never change.

[Leandro Cavalheiro]

But, I can't see usability in the class, why normally an class normally an table ... and make insert / update of data ...

[Leandro Cavalheiro]

But the question, have intention of understand, if exists any reason ....beyond the explicit motive that is to make immutable

[karelpeeters]

Are you asking about the general motivation for immutability? If an object is immutable you can pass it around freely without having to worry about someone else modifying it. Consider for example the String class, when I do something like this:

val a = "Test"
foo(a)
//here I'm 100% sure a is still "Test", foo couldn't have modified it

[Leandro Cavalheiro]

The motivation for immutablity..i understand ... my question referred the class.. if have any reason for always uses immutablity in the examples...

[karelpeeters]

It's pretty much the default: use val whenever you can and switch to var only if you really need a mutable variable.

[Leandro Cavalheiro]

Understand... thanks for explanation

[cedric]

@karelpeeters val and var are about making the references constant, they have nothing to do with making the object mutable/immutable /cc @Leandro Cavalheiro

[karelpeeters]

@cedric I misunderstood his question as "why is immutability useful?", so I tried to explain that. Thanks for clarifying!

[karelpeeters]

In hindsight my example was pretty bad too.