Questions tagged [call-by-need]
6 questions
21
votes
0 answers
Haskell: How "cache" friendly is Lazy Eval / call by need
I have been studying Haskell in my spare time for a couple of months now. I'm wondering how Haskell performs on the current stock hardware, in regards to the memory sub-system (L1, L2, L3 cache). Can someone please point me to any report/study on…
user3169543
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19
votes
3 answers
What is call-by-need?
I want to know what is call-by-need.
Though I searched in wikipedia and found it here: http://en.wikipedia.org/wiki/Evaluation_strategy,
but could not understand properly.
If anyone can explain with an example and point out the difference with…
Barshan Das
- 3,451
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5
votes
2 answers
Simple example of call-by-need
I'm trying to understand the theorem behind "call-by-need." I do understand the definition, but I'm a bit confused. I would like to see a simple example which shows how call-by-need works.
After reading some previous threads, I found out that…
vesii
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1
vote
1 answer
Call By Need in Scheme
I have this code knowing that parameters are passed using call by need:
(define fact-2
(let ((foo (lambda (n f)
(if (zero? n)
1
(f n f)))))
(lambda (n)
(let ((res 1))
(foo n…
Maya Saias
- 25
- 7
1
vote
1 answer
Call-by-need and call-by-name reduction relation semantics
While trying to summarize my knowledge about lambda calculus, I understood that I'm quite familiar with call-by-value but I've never seen сall-by-need reduction semantics. I know the definition, but it would be great to see precise meaning.
This is…
vonaka
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0
votes
0 answers
Counting infix operations executed under call-by-name and call-by-need
Provided the functions (from a lazy functional programming language perspective):
fun1(`n0`) = let `n1` = `n0` + `n0` in
let `n2` = `n1` + `n1` in
...
let x = `nn` + `nn` in
x
fun2(`n0`) = let…
NewDev90
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