Evaluation Order and Infinite Lists
- slide 7 : 27
Infinite evaluations and error evaluations - clarification
What is the value of the following expressions?
((lambda (x) 1)
some-infinite-calculation
) ((lambda (x) 1)
(/ 5 0)
)
Different evaluation orders give different 'results'
The number 1
A non-terminating calculation/an erroneous calculation
Two different semantics of function application are involved:
Strict
: A function call is well-defined if and only if all actual parameters are well-defined
Non-strict
: A function call can be well-defined even if one or more actual parameters cause an error or enters an infinite calculation
Scheme is strict
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