Reflection for enumerations in Objective-C.
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README.md

ReflectableEnum

Build Status Carthage compatible

A macro and a set of functions introducing reflection for enumerations in Objective-C.

Features:

  • get a string value for an enumeration's member (which is a common problem)
  • get all values used in an enumeration (also a prevalent issue)
  • get a minimum value in an enumeration
  • get a maximum value in an enumeration
  • get an enumeration's member for a string (if it exists)

Usage

Once you have ReflectableEnum added to your project, you just need to replace existing enum definitions, like:

typedef NS_ENUM(NSUInteger, AccountType) {
  AccountTypeStandard,
  AccountTypeAdmin
};

with:

REFLECTABLE_ENUM(NSInteger, AccountType,
  AccountTypeStandard,
  AccountTypeAdmin
);

Now you can get a string representing an enumerator and all/minimum/maximum values of an enumeration the enumerator belongs to with:

AccountType accountType = AccountTypeStandard;
NSString *typeString = REFStringForMember(accountType);          // @"AccountTypeStandard"
NSArray *allValues = REFAllValuesForEnumWithMember(accountType); // @[@0, @1]
NSInteger mininimum = REFMinForEnumWithMember(accountType);      // 0
NSInteger maximum = REFMaxForEnumWithMember(accountType);        // 1
AccountType accountType = REFMemberForString(accountType, @"AccountTypeAdmin"); // 1 (first argument is just for an enum type indication)

In case you pass the enumerator directly to one of these functions, you have to cast it to AccountType, because the compiler doesn't know its type (it's treated as NSInteger in this case):

NSString *typeString = REFStringForMember((AccountType)AccountTypeStandard);
NSArray *allValues = REFAllValuesForEnumWithMember((AccountType)AccountTypeStandard);
NSInteger mininimum = REFMinForEnumWithMember((AccountType)AccountTypeStandard);
NSInteger maximum = REFMaxForEnumWithMember((AccountType)AccountTypeStandard);
AccountType accountType = REFMemberForString((AccountType)0, @"AccountTypeAdmin"); // 1 (first argument is just for an enum type indication)

The need to cast is a hassle, so ReflectableEnum will create enum-specific functions for you too:

NSString *typeString = REFStringForMemberInAccountType(AccountTypeStandard);
NSArray *allValues = REFAllValuesInAccountType();
NSInteger mininimum = REFMinInAccountType();
NSInteger maximum = REFMaxInAccountType();
AccountType accountType = REFMemberForStringInAccountType((AccountType)0, @"AccountTypeAdmin");

As you can see names of these functions depend on the name of the enumeration and follow these patterns: REFStringForMemberIn\(enumName), REFAllValuesIn\(enumName), REFMinIn\(enumName), REFMaxIn\(enumName) and REFMemberForStringIn\(enumName).

Drawbacks

  • REFStringForMember and REFStringForMemberIn\(enumName) don't work with enumerations containing duplicated values, e.g. with self-referencing members AccountTypeModerator = AccountTypeAdmin
  • can't be used for enumerations already defined in frameworks and libraries

Requirements

  • iOS 7 and above
  • OS X 10.9 and above

Installation

Install with Carthage:

github "fastred/ReflectableEnum"

or with CocoaPods:

pod "ReflectableEnum"

And then import with: #import <ReflectableEnum/ReflectableEnum.h>

Author

Arkadiusz Holko: