Can you give an example for which the proposed syntax would be problematic? Your example would be written as: let a = [: [: 1, 2, 3 :], [: 6, 7, 8 :] :] o

Can you give an example for which the proposed syntax would be problematic? Your example would be written as: let a = [: [: 1, 2, 3 :], [: 6, 7, 8 :] :] or let a = [ [: 1, 2, 3 :], [: 6, 7, 8 :] ] etc., depending on what mutability you want.