This was originally meant as a convenience but prevents possible
functionality. For example:
-- Get the keys of the table with even values
local t = { a = 1, b = 2, c = 3, d = 4 }
vim.iter(t):map(function(k, v)
if v % 2 == 0 then return k end
end):totable()
The example above would not work, because the map() function returns
only a single value, and cannot be converted back into a table (there
are many such examples like this).
Instead, to convert an iterator into a map-like table, users can use
fold():
vim.iter(t):fold({}, function(t, k, v)
t[k] = v
return t
end)
9489406879
