Topic: mapcar or foreach

[MP]

[sidebar]
MP, it's rather ironic that you used 'ssget' to show that you use 'repeat' quite often when 'foreach' and 'mapcar' can't get 'ssget' entities.
[/sidebar]

In the spirit of fun ...

Code: [Select]

(defun PicksetToEnames ( ss / i result )
    (if (eq 'pickset (type ss))
        (repeat (setq i (sslength ss))
            (setq result
                (cons
                    (ssname ss (setq i (1- i)))
                    result
                )
            )
        )
    )
)

[CAB]

And more fun.
Well you used the "can't" word. he he he

Code: [Select]

;;  CAB 03/22/2005
;;  just an exersize
(defun c:TxtC (/ ss elst)
  (prompt "\nSelect text objects... <exit> ")
  (and (setq ss (ssget '((0 . "TEXT") (72 . 1) (73 . 2))))
       (repeat (sslength ss)
         (setq elst (entget (ssname ss 0)))
         (entmake (list '(0 . "CIRCLE")
                        (cons 10 (cdr (assoc 11 elst)))
                        (cons 40 (* (cdr (assoc 40 elst)) 0.06))
                  )
         )
         (ssdel (ssname ss 0) ss)
       )
  )
  (princ)
)

[LE]

Here are some samples using mapcar and foreach:

Code: [Select]

(defun rcmd-divide-vector  (pt1 pt2 n)
  (mapcar '+
  pt1
  (mapcar '/
  (mapcar '- pt2 pt1)
  (list n n n))))

(defun rcmd-transpts  (lst pt / p0 p1 ang pin ang pt1 lst1)
  (setq p0  (car lst)
p1  (cadr lst)
ang (angle p0 p1)
pin (inters p0 p1 pt (polar pt (+ ang (/ pi 2)) 1) nil)
ang (angle pin pt))
  (foreach
p
  lst
    (setq pt1  (polar p ang (distance pt pin))
  lst1 (append lst1 (list pt1))))
  lst1)

(defun rcmd-point-member  (p lst / tst)
  (foreach
pt
   lst
    (if pt
      (if (equal (distance p pt) 0 0.00001)
(setq tst T))))
  tst)

(defun rcmd-list->ss  (lst / ss0)
  (setq ss0 (ssadd))
  (foreach n lst (ssadd n ss0))
  ss0)

(defun rcmd-point-member  (p lst / tst)
  (foreach
pt
   lst
    (if pt
      (if (equal (distance p pt) 0 0.00001)
(setq tst T))))
  tst)

(defun rcmd-no-equal-points  (lst / lst2)
  (foreach
pt
   lst
    (if (not (rcmd-point-member pt lst2))
      (setq lst2 (append lst2 (list pt)))))
  lst2)


[LE]

another one:

Code: [Select]

;; string_lst = list of strings
;; flag = max or' min
(defun strlenmm (string_lst flag / lst)
  (setq lst (mapcar (function (lambda (x) (cons (strlen x) x)))
    string_lst))
  (cdr (assoc (apply 'flag (mapcar 'car lst)) lst)))

_$ (strlenmm (list "10000.0" "1.0" "2300000000" "1.234") min)
"1.0"
_$
_$ (strlenmm (list "10000.0" "1.0" "2300000000" "1.234") max)
"2300000000"
_$


[Jeff_M]

Will you used the "can't" word. he he he

Maybe I misread that, but I thought he was referring to the fact you can't do

Code: [Select]

(foreach ent ss ....)
(mapcar 'entget ss)


[MP]

That's the way I read it too Jeff, ergo ..

(foreach ename (PicksetToEnames (ssget "x"))
    (foo ename)
)

Or ...

(mapcar 'foo (PicksetToEnames (ssget "x")))

[CAB]

OK, i understand now, Little slow on the uptake lately.

And this doesn't count, right?

Code: [Select]

(foreach ename (mapcar (function cadr) (ssnamex ss))
Well I tried,

[Kerry]

Hi CAB,

In your c:TxtC, I found it interesting that you progressively popped the first item from the selection set
at each iteration and called (entget (ssname ss 0)))
rather than create an incrementing counter as an index into a static selectionset. 

[CAB]

Thanks for noticing.
That was the deference I was trying to show from Michael's example above it.
I should have dressed it up a bit as pretty does not come naturally to me as you know.
It was an exercise in ways to iterate through a selection set and that was one of them.
As you know deleting from a selection set if you are not careful can produce unwanted results.

[whdjr]

Will you used the "can't" word. he he he

Maybe I misread that, but I thought he was referring to the fact you can't do

Code: [Select]

(foreach ent ss ....)
(mapcar 'entget ss)


Thanks for helping me get my point across Jeff.

I thought I was gonna have to clarify myself.

 

[whdjr]

In the spirit of fun ...

Code: [Select]

(defun PicksetToEnames ( ss / i result )
    (if (eq 'pickset (type ss))
        (repeat (setq i (sslength ss))
            (setq result
                (cons
                    (ssname ss (setq i (1- i)))
                    result
                )
            )
        )
    )
)

That's the way I read it too Jeff, ergo ..

(foreach ename (PicksetToEnames (ssget "x"))
    (foo ename)
)

Or ...

(mapcar 'foo (PicksetToEnames (ssget "x")))

Michael,

This just further illustrates my point that you can't get at the entities in a 'ssget' selection set.

I just thought it was funny that LE's statement that 'repeat' seems to be forgotten by most people was responded by you with an example of a situation of where the only way to get at the data in the example was to use repeat- which was the only method of the 3 previously mentioned methods that would have worked in this occurance.

 

[LE]

Code: [Select]

(setq ss (ssget))
(vlax-for
       item
      (vla-get-activeselectionset
(vla-get-activedocument (vlax-get-acad-object)))
  (print item))


[LE]

Code: [Select]

(vlax-for
       item
      (vla-get-activeselectionset
(vla-get-activedocument (vlax-get-acad-object)))
  (print (entget (vlax-vla-object->ename item))))


[Fatty]

Code: [Select]

(setq ss (ssget))
(vlax-for
       item
      (vla-get-activeselectionset
(vla-get-activedocument (vlax-get-acad-object)))
  (print item))


I use the following one without declaring of ss:

Code: [Select]

(ssget)
(vlax-for
       item
      (vla-get-activeselectionset
(vla-get-activedocument (vlax-get-acad-object)))
  (print item))


[LE]

I use the following one without declaring of ss:

Code: [Select]

(ssget)


Yep... we don't need the ss var..... I am doing this samples on the fly [like mickey-mouse code].... 

Thanks.