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History of Idiom 20 > diff from v18 to v19

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Version 18

2015-09-04, 19:16:44

Version 19

2015-09-04, 19:23:04

Idiom #20 Return two values

Implement a function search which looks for item x in a 2D matrix m.
Return indices i, j of the matching cell.
Think of the most idiomatic way in the language to return the two values at the same time.

Idiom #20 Return two values

Implement a function search which looks for item x in a 2D matrix m.
Return indices i, j of the matching cell.
Think of the most idiomatic way in the language to return the two values at the same time.

Code 
searcb x m = let i = findIndex (elem x) m; j = elemIndex x (m!!i) in (i, j)
Code 
searcb x m = head [ (i, j) | (i, r) <- zip [0..] m,
					(j, c) <- zip [0..] r, c == x]