[Haskell-beginners] variables in haskell

Brandon S. Allbery KF8NH allbery at ece.cmu.edu
Mon Oct 13 22:32:29 EDT 2008

On 2008 Oct 13, at 2:58, Matthew J. Williams wrote:
> Hello listers, would one be correct in thinking that 'bound  
> variables' such as those used in haskell were in fact constants?

Only in certain limited circumstances.  Consider the following:

 > let x = f x in x

This finds the least defined fixed point of f.  See < http://en.wikibooks.org/wiki/Haskell/Fix_and_recursion 

Top level constant applicative forms (that is, bindings without  
arguments) with monomorphic types can generally be considered to be  
constants, and the compiler may assume this and inline it.  But it's  
not required to do so.

brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH

More information about the Beginners mailing list