With/EndWith integrated to ForEach/Next

Flype · Post by **Flype** » Tue Jan 16, 2007 8:51 pm

A small snippet is better than a long explanation. All is in the title and the snippet :

I'm not sure if it's a good idea - maybe yes maybe no - just discuss about it.

Code: Select all

Structure PRODUCT
  id.s
  name.s
  price.s
  desc.s
EndStructure

Global NewList product.PRODUCT()

ForEach product()
  With product()
    Debug "id = "    + \id
    Debug "name = "  + \name
    Debug "price = " + \price
    Debug "desc = "  + \desc
    Debug ""
  EndWith
Next

ForEach product()
  Debug "id = "    + \id     ; <--------- Syntax Error.
  Debug "name = "  + \name
  Debug "price = " + \price
  Debug "desc = "  + \desc
  Debug ""
Next

Trond · Post by **Trond** » Tue Jan 16, 2007 8:54 pm

I once suggested this and people thought it was dreadful. But I think it's a good idea.

Kaeru Gaman · Post by **Kaeru Gaman** » Tue Jan 16, 2007 8:57 pm

hm... *shrug*

could be useful, but the leading backslash looks strange to me..

think i won't use it. copy/paste of the listname is sufficent ....

AND51 · Post by **AND51** » Tue Jan 16, 2007 9:22 pm

There is something similar in CGI - very useful.

Code: Select all

ForEach myArray()
     print $_;
next

$_ is the abbreviation for the currently used array in CGI/Perl.

I would appreciate this request, if there are no conflicts with other commands and if I still can access another linked list in that foreach/next loop.

Peaople like Kaeru Gaman, who don't like this, can still use myList()\id, etc within the foreach/next.

remi_meier · Post by **remi_meier** » Tue Jan 16, 2007 9:53 pm

No way!

Code: Select all

NewList ll.Long()
NewList ll2.Long()

ForEach ll()
  ForEach ll2()
    \l = 4
  Next
Next

Flype · Post by **Flype** » Tue Jan 16, 2007 10:50 pm

Hi remi_meyer.

No Way ! Hmmmm, Why ?

Code: Select all

NewList ll.Long()
NewList ll2.Long()

ForEach ll()
  \l = 1        ; same as ll()\l
  ForEach ll2()
    \l = 4      ; same as ll2()\l
  Next
Next

ForEach ll()
  ForEach ll2()
    ll()\l = 4  ; if you need to use ll() in ll2()
  Next
Next

remi_meier · Post by **remi_meier** » Tue Jan 16, 2007 10:53 pm

That's just a mess...
Do you see the reason, why With-EndWith is not nestable?

Flype · Post by **Flype** » Tue Jan 16, 2007 11:25 pm

Yes, i can easily imagine the mess for the pre-processor and for the pre-pre-processor (Fred/Freak).

I'm just discussing...

Kaeru Gaman · Post by **Kaeru Gaman** » Tue Jan 16, 2007 11:33 pm

well... let me add the mess for the readability of your code...

nco2k · Post by **nco2k** » Wed Jan 17, 2007 4:48 am

i think its a bad request.

if you want to use it that much, then simply write:

Code: Select all

ForEach List()
  With List()
    \Element = 0
  EndWith
Next

i totally agree with remi.

c ya,
nco2k

Hroudtwolf · Post by **Hroudtwolf** » Wed Jan 17, 2007 6:25 am

Code: Select all

Macro ForEachWith (_LIST_)
  ForEach _LIST_ : With _LIST_
EndMacro

Macro NextWith 
  EndWith : Next
EndMacro

NewList test ()

AddElement (test ()):test()=1
AddElement (test ()):test()=2
AddElement (test ()):test()=3
AddElement (test ()):test()=4

ForEachWith (test ())
  Debug test ()
NextWith

SCRJ · Post by **SCRJ** » Wed Jan 17, 2007 10:27 am

No, in version 4.02, you can't use "with" in macros.
Have a look on this topic

http://www.purebasic.fr/english/viewtopic.php?t=25273

Joakim Christiansen · Post by **Joakim Christiansen** » Mon Apr 16, 2007 6:33 pm

I agree that a With integrated in the ForEach loop would be nice.
Something like this:

Code: Select all

ForEach With Apples()
  ;bla bla
Next

The compiler should then see that With is used in the ForEach loop and end it at the Next command. I think this is the best way to do it? Fred?

jear · Post by **jear** » Tue Apr 17, 2007 12:25 am

What is intended to be the higher abstraction level: ForEach or With?

Code: Select all

Structure Leute
  Name.s
  Vorname.s
  Strasse.s
  PLZ.s
  Ort.s
EndStructure

NewList Leute.Leute()

With Leute()
  ForEach
    \PLZ = "26160"
  Next
EndWith