List.Generate

List

Generates a list of values using an initial value, a condition, a next function, and an optional selector.

Syntax

List.Generate(initial as function, condition as function, next as function, optional selector as nullable function) as list

Parameters

Name	Type	Required	Description
`initial`	`function`	Yes	A function that returns the initial state value.
`condition`	`function`	Yes	A function that returns true to continue generating, false to stop.
`next`	`function`	Yes	A function that produces the next state value from the current state.
`selector`	`function`	No	An optional function that transforms each state value into the output value.

Return Value

list — A list of generated values.

Remarks

List.Generate creates a list by repeatedly applying a "next" function to a state value, continuing while a condition is true. It is M's equivalent of a while loop.

Common use cases include generating date sequences, paginating API calls, and building custom number ranges.

Examples

Example 1: Generate a date range

let
    StartDate = List.Min(Table.Column(Sales, "OrderDate")),
    Dates = List.Generate(
        () => StartDate,
        each _ <= Date.AddDays(StartDate, 4),
        each Date.AddDays(_, 1)
    )
in
    #table({"Date"}, List.Transform(Dates, each {_}))

Result

	Date
1	1/15/2024
2	1/16/2024
3	1/17/2024
4	1/18/2024
5	1/19/2024

Compatibility

✓ Power BI Desktop✓ Power BI Service✓ Excel Desktop✓ Excel Online✓ Dataflows✓ Fabric Notebooks