LispForum

Your code did not work in my implementation. But here is my solution of what you probably wanted: (defmacro cond-clause (expr res) `(,expr (push ,res res) ) ) (defmacro test (cond-expr) `(cond ,(macroexpand-1 cond-expr) ) ) Then the command (macroexpand-1 '(test (cond-clause (equalp c 8) 1) ) ) resu...

When dealing with functions in LISP it is sometimes desirable to handle them differently depending on the number of formal variables. My question: is there any possibility to define classes of functions like "functions_of_one_variable", "functions_of_two_variables" etc? If this w...

Take a look at this discussion:
http://computer-programming-forum.com/5 ... 7dbc58.htm

When formulating your problem, you should also think about lexical closures. Assume your piece of LISP code contains the following fragment: (flet ((list (&rest argument) ......... definition ..........)) (LIST a b) (LIST c d e) .... et cetera ...... ) Are you sure you want to replace function o...

I am not so advanced LISP user to understand the difference between a runtime evaluation and a macroexpansion out (:-)))) But macro TRUE-EVAL has indeed a strange behaviour. It cannot be applied to formal variables inside function definitions, an attempt to compile (defun t-eval (x) (true-eval x) ) ...

The discussion in this topic is aimed at better understanding how the principle "there is no difference between code and data in LISP" works in practice. My intention was to "execute" comand-variables containing LISP code as their values (like variable "command") so tha...

After some experiments I found a right replacement of EVAL operator which works as expected inside lexical closures. This is the following macro: (defmacro true-eval (command-expression) `(macrolet ((evaluate () ,command-expression)) (evaluate) )) Here is a testing code: (setf command '(+ c j) ) (se...

Thank you for the explanation! I would say this is not so economic behaviour of LISP processor,
to run first all available methods and then to choose appropriate result. It seems much more natural to choose first
appropriate method and then to run it.

Situation is not so easy. The code (defmethod initialize-instance :after ( (item Big) &key ) (setf (my-value item) 666 ) ) (setf x (make-instance 'Small ) ) results in creating an instance "x" having my-value 13, as expected since the method of initialization for the class "Small&...

I try to experiment with classes in LISP and I stuck at the following problem already at a very beginning level. I define two classes "BIg" and "Small" so that "Small" is a subclass of "Big": (defclass Big () ( (my-value :accessor my-value) )) (defclass Small ...