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+# Trait
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+
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+A trait/typeclass system for Scheme.
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+
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+## Example
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+
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+ (import trait)
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+
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+ (define-record point x y)
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+
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+ (define-trait Eq
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+ ;; fallback to equal? by default
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+ (same? equal?))
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+
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+ (define-trait-impl (Eq number?)
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+ (same? =))
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+
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+ (define-trait-impl (Eq symbol?)
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+ (same? eq?))
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+
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+ (define-trait-impl (Eq point?)
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+ (same? (lambda (a b) (and (point? b)
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+ (= (point-x a) (point-x b))
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+ (= (point-y a) (point-y b))))))
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+
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+ (display (list (same? 'a 'a)
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+ (same? 1 1)
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+ (same? 1 2)
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+ (same? (list 1 2) (list 1 2))
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+ (same? (cons 3 4) (cons 3 4))
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+ (same? (make-point 1 2) (make-point 3 4))))
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