Stupid Macro Tricks™

gistfile1.m

// TsImageSizeConstraintType is an enum with these four values:
#define MAP \
ENTRY(TsEditionImageSizeConstraintNone) \
ENTRY(TsEditionImageSizeConstraintDimensions) \
ENTRY(TsEditionImageSizeConstraintPixelCount) \
ENTRY(TsEditionImageSizeConstraintByteCount)

NSString * TsStringForImageSizeConstraintType(TsImageSizeConstraintType type) {
    switch(type) {
#define ENTRY(TYPE) case TYPE: return @#TYPE;
        MAP
#undef ENTRY
    }
}

TsImageSizeConstraintType TsImageSizeConstraintTypeFromString(NSString * string) {
    static NSDictionary * table;
    static dispatch_once_t once;
    
    dispatch_once(&once, ^{
#define ENTRY(TYPE) @#TYPE : @(TYPE),
        table = @{ MAP };
    #undef ENTRY
    });
    
    return [table[string] integerValue];
}

#undef MAP