Re: diff. betw. equal and eq on simbols
Nikola Skoric wrote:
> I've been reading "COMMON LISP: A Gentle Introduction to Symbolic
> Computation" by David S. Touretzky, and came across a section where he
> describes difference between eq and equal. And, says "Due to its greater
> efficiency, programmers often use EQ instead of EQUAL when symbols are
> being compared." Now, why would eq be more efficient than equal when
> comparing only one symbol?
eq is generally more effecient than equal. However, as it compares
actual memory addresses of the two objects, it has a much stricter
definition of equality to equal, so you should only use it when you
want to compare symbols, or check that two things are the *same* object.
.
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