User blog comment:Vel!/Ellipsis considered harmful/@comment-27394924-20170605172751/@comment-30754445-20170605174137

Seconded.

I find the whole "never use X" adage to be silly. Definitions should be clear and readable, and achieving this is difficult enough without trying to obey a set of arbitrary rules.

In fact, looking at the examples that Vel! gave, I find:

a {c+1} b = a {c} a {c} ... (with 'a' repeated b times) ... {c} a {c} a

to be far clearer than

{a,b+1,c+1} = {a,{a,b,c+1},c}

(note my rephrasing of the first statement, though)