• Per =?UTF-8?B?Tm9yZGzDtnc=?= (7/7) Nov 14 2018 Why is there at
• Dennis (11/13) Nov 14 2018 chunkBy splits the range into smaller ranges, group actually

Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

Why is there at

https://dlang.org/phobos/std_algorithm_iteration.html

an inconsistency in naming of `group` and chunkBy`?

Is it because of `group` has a default for the predicate whereas 
`chunkBy` hasn't.

Further, why aren't the two merged into a single iteration 
algorithm?

Dennis <dkorpel gmail.com> writes:

On Wednesday, 14 November 2018 at 12:28:38 UTC, Per Nordlöw wrote:
 Is it because of `group` has a default for the predicate 
 whereas `chunkBy` hasn't.

chunkBy splits the range into smaller ranges, group actually 
returns tuples of the item and the amount of occurences. Because 
in group the condition is fixed to equality, it's redundant to 
return a range of [2, 2, 2, 2, 2, 2] for example when you can 
simply return a tuple (2, 6).

The example:
group([5, 2, 2, 3, 3]) returns a range containing the tuples 
tuple(5, 1), tuple(2, 2), and tuple(3, 2).

Is a bit confusing since tuple(2, 2) looks like it could be a 
range of two 2's as well.