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Scheme vs Common Lisp style in SKILL++

tweeks

 While you can write your SKILL++ code like it is C, Maclisp, Scheme, or Common Lisp (or none of the above...), I've been experimenting with Common Lisp style lately.

Trying to write Common Lisp style code in SKILL++ can lead to curious situations like this:

(defvar first car)

The intention is to define FIRST as another name for CAR, as in Common Lisp.  In Scheme, we would write

(define first car)

which seems pretty natural, but using DEFVAR to define a function just feels.... wrong... somehow... :)

I guess I should use ALIAS:

 (alias second cadr)

 except ALIAS has weird limitations:

ILS-> (foo = first)
primop:car
ILS-> (foo '(1 2 3))
1
ILS-> (foo = second)
macro:evalalias
ILS-> (foo '(1 2 3))
*Error* evalalias: unknown alias - foo

Parents
  • theopaone

     The only differences I have with Andrew are:

    1. Constants are a formal concept in my programs. They are write protected uppercase global symbols which have a value shared in SKILL and SKILL++.  Constants are common values such as rotations R0, R90, etc. Even the abutment function values are constants SERIES_CONNECT, PARALLEL_CONNECT, UN_ABUT, ... , ABUT_LEFT, ABUT_RIGHT etc. each resolving to their respective integer values. That way I don't have to remember what the actual value.

    2. recursion is a monster to debug, especially if the code is not directly recursive -> A calls B calls C calls A. I prefer the iteration constructs, they could be improved if they were real iterators instead of having to build a list in VM.

    3. Without a break or continue for loops, go is somewhat but seldom useful. My first language was Fortran IV with goto's, on punch cards, almost prehistoric school.

    Ted

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  • theopaone

     The only differences I have with Andrew are:

    1. Constants are a formal concept in my programs. They are write protected uppercase global symbols which have a value shared in SKILL and SKILL++.  Constants are common values such as rotations R0, R90, etc. Even the abutment function values are constants SERIES_CONNECT, PARALLEL_CONNECT, UN_ABUT, ... , ABUT_LEFT, ABUT_RIGHT etc. each resolving to their respective integer values. That way I don't have to remember what the actual value.

    2. recursion is a monster to debug, especially if the code is not directly recursive -> A calls B calls C calls A. I prefer the iteration constructs, they could be improved if they were real iterators instead of having to build a list in VM.

    3. Without a break or continue for loops, go is somewhat but seldom useful. My first language was Fortran IV with goto's, on punch cards, almost prehistoric school.

    Ted

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