Re: variable exchange

Patricia Shanahan wrote:
I've known the technique for about 20 years. I have yet to encounter a
situation in which I've needed to use it.

I think I used it once. In Z80 assembler. There, and maybe in the IOCCC it might have its place.

Oh, and a variant is useful in interactive computer graphics. To draw a cursor on top of some graphics and to erase the cursor later, without having to remember the graphics contents under the cursor.

/Thomas
--
The comp.lang.java.gui FAQ:
http://gd.tuwien.ac.at/faqs/faqs-hierarchy/comp/comp.lang.java.gui/
ftp://ftp.cs.uu.nl/pub/NEWS.ANSWERS/computer-lang/java/gui/faq
.

Relevant Pages

  • Re: making a very simple menu in DOS
    ... Since you will probably want to high-light the item when the cursor is over it and need to know where the magic key is pressed anyway you also must read the bios to obtain the cursor location on the screen. ... switch to a graphics mode, paint some labeled buttons and use the mouse to select a menu item? ... If the click is over an item you placed on the screen switch the screen back to text mode and run the item's code or spawn it out to DOS. ... your C package should include some mouse and graphics routines. ...
    (comp.os.msdos.programmer)
  • Re: ASCII Editor
    ... garyr wrote: ... I just can't get the cursor to go where I wanted. ... It works fine if all you want to use are the predefined graphics but it ... I believe that an ASCII editor should first ...
    (sci.electronics.design)
  • Re: My mouse pointer becomes 8 dots -- heres the video
    ... I use Windows XP Pro, Version 2002, with Service Pack 2. ... relies on software other than the mouse driver. ... On some graphics subsystems, the cursor is an actual hardware ...
    (microsoft.public.windowsxp.hardware)
  • Re: My mouse pointer becomes 8 dots -- heres the video
    ... I use Windows XP Pro, Version 2002, with Service Pack 2. ... relies on software other than the mouse driver. ... On some graphics subsystems, the cursor is an actual hardware ...
    (microsoft.public.windowsxp.hardware)
Loading