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digitalmars.D.learn - What's the diff between immutable and const?

reply "XCPPCoder" <xcelsior jupitor.com> writes:
What's the diff between immutable and const?
Apr 22 2010
next sibling parent "Simen kjaeraas" <simen.kjaras gmail.com> writes:
XCPPCoder <xcelsior jupitor.com> wrote:


 What's the diff between immutable and const?


Basically, const means 'I can't change this', while immutable means 'nobody
will change this'.
The idea is that const is a guarantee given by a function, while immutable
is a guarantee for the whole program. Also, immutable opens up optimization
possibilities, as you can safely assume the data is not going to change
under you. That means read once, and no locks necessary.

-- 
Simen
Apr 22 2010
prev sibling parent =?UTF-8?B?QWxpIMOHZWhyZWxp?= <acehreli yahoo.com> writes:
XCPPCoder wrote:

 What's the diff between immutable and const?


Very shortly: immutable means "never changes", "const" means "may not be 
changed through this reference".

Some more information:

   http://www.digitalmars.com/d/2.0/const3.html

Ali
Apr 22 2010