Databases
StackOverflow2013
Postsdbo
POHow to write a function or macro for "oneOf" ... casting in variadics?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to write a function or macro for "oneOf" ... casting in variadics?
    primarykey
    data
    text
    <p>Note - using variadic arguments, <strong>Phix</strong> has provided a super solution below. However it gives compiler warnings when used with integers since you're casting them to an id, and it will not work with for example floats.</p> <p>Question -- how write a facility that chooses one item from a list? Ideally, it would be as flexible as possible <strong>regarding the type</strong> of the items/objects/whatever in the list.</p> <p>Example usage:</p> <pre><code>NSInteger openingMap = [utilities oneOf:1, 2, 3, 7, 8]; initialAngle =oneOf(1.25, 1.75, 1.95, 2.00, 2.01); self.spaceShipNickName =oneOf(@"Blaster",@"Blitzen",@"Stardancer",@"Quantum"); self.chassisProperty = oneOf(titanium, neutronium, unavailablium); [fireworksLayer paintStars:oneOf(blue,green,white) howMany:oneOf(20,25,50)]; [trump chooseDefaultSuite:oneOf(diamonds,hearts,clubs,spades)]; // normally have a few explosions, but, occasionally have a huge display... explosionCount = oneOf( 2,2,2,3,4,1,28,3,3,3,70 ); </code></pre> <p>Note that some examples are integers, some enums, some NSStrings, etc. So again, it would be most impressive if the one facility could handle different types. (Rather than perhaps a related group, like ... oneOfIntegers, oneOfStrings, oneOfObject, whatever.)</p> <p>It goes without saying that to choose the random item, just use...<br> = arcrandom() % number-of-items</p> <p>You could use <strong>an Objective C method or class, a c function, or some sort of system of macros, category extension to NSMutableArray, or indeed blocks - or anything else.</strong> It should be as flexible as possible for broad use anywhere in a typical iOS or Mac project... any ideas?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USFattie
    1. USFattie
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to write a function or macro for "oneOf" ... casting in variadics?
      1. USpetert
      1. VTFavorite
    2. VO
      singulars
      1. POHow to write a function or macro for "oneOf" ... casting in variadics?
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POHow to write a function or macro for "oneOf" ... casting in variadics?
      1. This table or related slice is empty.
      1. VTDownMod
    1. COok.. i don't think this question fits here... read FAQ#2... but if you really want people to answer this question just for the sake of 'challenge', start a bounty and then see how many answers you get...
      singulars
      1. POHow to write a function or macro for "oneOf" ... casting in variadics?
      1. USlukya
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload