each for filters

Run a closure on each row of the input list, creating a new list with the results.

Signature

> each (closure) --keep-empty

Parameters

• closure: the closure to run
• --keep-empty (-k): keep empty result cells

Notes

Since tables are lists of records, passing a table into 'each' will iterate over each record, not necessarily each cell within it.

Avoid passing single records to this command. Since a record is a one-row structure, 'each' will only run once, behaving similar to 'do'. To iterate over a record's values, try converting it to a table with 'transpose' first.

Examples

Multiplies elements in the list

> [1 2 3] | each {|e| 2 * $e }
╭───┬───╮
│ 0 │ 2 │
│ 1 │ 4 │
│ 2 │ 6 │
╰───┴───╯

Produce a list of values in the record, converted to string

> {major:2, minor:1, patch:4} | values | each {|| into string }
╭───┬───╮
│ 0 │ 2 │
│ 1 │ 1 │
│ 2 │ 4 │
╰───┴───╯

Produce a list that has "two" for each 2 in the input

> [1 2 3 2] | each {|e| if $e == 2 { "two" } }
╭───┬─────╮
│ 0 │ two │
│ 1 │ two │
╰───┴─────╯

Iterate over each element, producing a list showing indexes of any 2s

> [1 2 3] | enumerate | each {|e| if $e.item == 2 { $"found 2 at ($e.index)!"} }
╭───┬───────────────╮
│ 0 │ found 2 at 1! │
╰───┴───────────────╯

Iterate over each element, keeping null results

> [1 2 3] | each --keep-empty {|e| if $e == 2 { "found 2!"} }
╭───┬──────────╮
│ 0 │          │
│ 1 │ found 2! │
│ 2 │          │
╰───┴──────────╯