Special keyword to define mapping functions in expressions about mavo HOT 3 OPEN

They allow for a special CurrentValue keyword, which essentially represents the closest list item. In Mavo’s syntax, presumably this could be $value or $current.

Correct me if I’m wrong, but we already have $item, which represents exactly what you described—the closest list item. Can’t we simply re-use it? What am I missing?

$item (and $this) are fixed within the same execution: they refer to data from the nearest node that matches certain criteria. $value has no meaning outside iterative functions, which loop over a list and $value refers to the current value each time.

Some examples (assume we had map() and sort() functions):

Hypotenuse using numbers in a list:

sqrt(sum(map(numbers, pow($value, 2))))

Filter a list and only keep even numbers:

filter(numbers, $value mod 2 = 0)

Single line pivot table: From a list of flights, to stats about outbound airports:

map(flights by outbound, group(outbound: $value.outbound, count: count($value.$items))

This can already be expressed with current syntax like so:

filter(numbers, numbers mod 2 = 0)

or

numbers where numbers mod 2 = 0

Similarly, it enables patterns like

people.sort($value.name, "asc")

(map each person to their name, then sort based on that)

from mavo.

They allow for a special CurrentValue keyword, which essentially represents the closest list item. In Mavo’s syntax, presumably this could be $value or $current.

Correct me if I’m wrong, but we already have $item, which represents exactly what you described—the closest list item. Can’t we simply re-use it? What am I missing?

from mavo.

Makes sense. Thank you!

from mavo.