Haskell: List Comprehensions and higher-order functions -


I have tried to change the following list understanding: 

  f xs = [x +8 |  
 My first solution was:  
  f (x, _) and lt; -xs]   
. 'Xs = map (\ (x, _) -> x + 8) xs   
 After trying several other approaches, I came to know that it also works :  
  f 'xs = map ((+ 8) .fst) xs   
 both versions of  f  same (Correct) output, but I do not understand why  (+8) .fst  is equal to  \ (x, _) -> gt; X + 8 when using  map  on the list of tuples.  
  
 
 
  fst  definition  
  fst :: (a, b) - & gt; One FST (A, _) = a   
 and  (.) Is defined as   
  (.) :: ( B -> C) - & gt; (A -> B) - & gt; A - & gt; C (fg) = \ x - & gt; F (gx)   
 If we use these definitions to expand our work, then we should  
  f 'xs = map ( +8) .fst. Xs f 'xs = map (\ x - & gt; (+8) (fst x)) - Definition of x - f' xs = map (\ x - & gt; (+8) ((, _ ) - & gt; a) x) - fst f 'xs = definition of map (\ (a, _) -> (+8) a) - We can specify the pattern' f 'xs = map \ (a, _) ) - & gt; a + 8) - extension section

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