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Comment by dennis_vartan | Hacker News Reader

Like! Much as I love ObjC, reducing verbosity via better syntax can go a long way to making code more readable.

For example, I ended up putting together some defines like this after building a bunch of UI programmatically.

  #define RGB(r, g, b)     [NSColor colorWithDeviceRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:1]
  #define RGBA(r, g, b, a) [NSColor colorWithDeviceRed:(r)/255.0 green:(g)/255.0 blue:(b)/255.0 alpha:(a)]

RGB(255, 104, 0) may be a bit too C-ish, but it sure beats the long form. Have similar GRAY(x) and GRAYA(x) defines for producing grayscale colors.

Definitely interested to see more projects along these lines.

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I prefer:

    #define RGB(color)                        \
        (((color & 0xFF0000) >> 16) / 255.f), \
        (((color & 0x00FF00) >> 8) / 255.f),  \
        (((color & 0x0000FF)) / 255.f)

Pass in an HTML-style color hex triplet.

    #define RGB(r,g,b) RGBA(r,g,b,1)

I wrote a utility class with idiomatic Obj-C color methods like the one you mentioned and more. I hate to plug it, but I'm fairly proud of it. It also generates color schemes when you throw a UIColor object at it, and includes 100 different UIColor generics like [UIColor seafoamColor].

https://github.com/bennyguitar/Colours-for-iOS

Why on Earth would you hate to plug this? I could definitely see someone using this and being thankful they don't have to do it themselves. Hell, I'd use it if I hadn't already done my own category.

Suggestions: you might want to allow for three-digit hex strings and eight/four digit hex strings with alpha, I found that convenient in mine. And in the documentation it would be way cool if you made the names of the colors self-referential.

Nits: I would have made all the system color methods like "systemThingColor", capitalized RGB and HSB, and made "RGBDictionary" return @{@"red": ...} (and made static NSStrings for the keys so nobody needs to go to the .m file to see what will happen). Obviously I am a pedant and I live right on the edge of the 80 character limit; of these I'd only suggest making static dictionary keys as an actually desirable change.

Nice work, you shouldn't be ashamed to share it at all.

looks really nice, looking forward to using it!

I use a few like this in some of my helper macros[0] that I usually pull into my iOS projects.

[0]: https://gist.github.com/numo16/3407652

I use the same thing to construct NSDecimalNumber instances. N(100.5) instead of [NSDecimalNumber decimalNumberFromString:@"100.5"]

SO handy.

You can do this now @(100.5) for NSNumber literals.

And even shorter, just @100.5 if what you have is a literal. The parentheses are needed if you're boxing a value, e.g.: @(price + 100.5)

In detail: http://clang.llvm.org/docs/ObjectiveCLiterals.html

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