define class <vehicle> (<object>)
  slot owner :: <string>,
    init-keyword: owner:,
    init-value: "Northern Motors";
end class <vehicle>;

define class <car> (<vehicle>)
end class <car>;

define class <truck> (<vehicle>)
  slot capacity,
    required-init-keyword: tons:;
end class <truck>;

define generic tax
    (v :: <vehicle>) => (tax-in-dollars :: <float>);

define method tax
    (v :: <vehicle>) => (tax-in-dollars :: <float>)
  100.00
end;

define method tax
    (c :: <car>) => (tax-in-dollars :: <float>)
  50.0;
end method;

define method tax
    (t :: <truck>) => (tax-in-dollars :: <float>)
  // standard vehicle tax plus $10/ton
  next-method() + t.capacity * 10.0;
end method;

define function make-fibonacci()
  let n = 0;
  let m = 1;
  method ()
    let result = n + m;
    n := m;
    m := result  // return value
  end
end;

define constant fib = make-fibonacci();

for (i from 1 to 15)
  format-out("%d ", fib())
end;

‹ ›

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Updated Dylan Programming Guide — 2013-01-21

The Dylan Programming Guide has been updated to our new documentation format and is now available in PDF and ePub formats.

New release: 2012.1 — 2012-12-20

We just released Open Dylan 2012.1. This release brings many bugfixes, improved platform support and new features.

Improved editor support — 2012-10-18

Bugs in the syntax highlighting support for Textmate and Sublime Text as well as for vim have been fixed.

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• Introduction to Dylan:

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• Dylan Programming Guide:

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• Dylan Reference Manual:

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• Open Dylan Documentation:

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