[Rd] Scope problem?

Duncan Murdoch murdoch at stats.uwo.ca
Sat May 23 01:32:49 CEST 2009

On 22/05/2009 3:02 PM, Barry Rowlingson wrote:
> On Fri, May 22, 2009 at 6:04 PM, Duncan Murdoch <murdoch at stats.uwo.ca> wrote:
>> Putting force(xl); force(yl) into your interpOne definition (so they get
>> executed when interpOne is called, not just when the returned function is
>> called) should work.
>  *sigh* yes, that looks like it. The help for "force" gives a more
> concise example. What I'd posted was actually a cut-down version of my
> original problem!
>  I've not tested it yet, but other things I'd tried had removed the
> bug without me understanding why - such as reassinging the args to
> interpOne inside the function.
>  Do any other languages work like this?

According to Wikipedia (http://en.wikipedia.org/wiki/Lazy_evaluation), 
functional languages tend to do this; examples they give are Haskell, 
Miranda, and it's optional in Scheme and Ocaml.

Duncan Murdoch

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