w33zel

## Map, FlatMap (CompactMap), Reduce, Filter & Sort.md

      
        
          
            
              
              1 file
            
          
          
            
              
              5 forks
            
          
          
            
              
              3 comments
            
          
          
            
              
              18 stars
            
          
        
        
          
              
          
          
            
                SheldonWangRJT
                / Map, FlatMap (CompactMap), Reduce, Filter & Sort.md
            
            
              Last active
              March 21, 2022 20:04
            
              
                Swift Map, FlatMap (CompactMap), Reduce, Filter & Sort
              
          
        
      
        
  
      
    High Order Functions in iOS Swift

Written by Sheldon, please find me with #iOSBySheldon in Github, Youtube, Facebook, etc.
It is exaggerating to say  we don't need to use for loop or while loop any more but we can take advantage of the Swift language built in functions to do loops. If I give you a question now.
Q: Assuming we have an optional nested array, please calculate the production of the values that are less than 5. let numbers: [[Int]?] = [[1, 3], nil, [2], [5, 10], nil, [4]], what is your best approach to do it?
And you know the solution that I am talking about is following Swift functions:

Map
FlatMap / CompactMap