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4 points by conanite 5180 days ago | link | parent

(a) might look funny when you want to evaluate an expression for the default value of an optional arg

  (def foo (a b '(c (defaults 'c x y z)) ...
To the untrained eye, (defaults 'c x y z) looks like it should not be evaluated because it's quoted

(c) makes parsing harder ... the assumption of only one element after the dot may be built into the parser

  arc> '(a b c . d e)
  Error: "UNKNOWN::8: read: illegal use of `.'"
It could be some privileged symbol instead of "." though ...


1 point by akkartik 5180 days ago | link

Great points. I realized c was breaking the metaphor of '.'; I didn't realize it would actually refuse to parse.

It doesn't make sense to quote forms that may have expressions to evaluate, so b is better than a.

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