ConstReadonlyCopy: { filler: Copy; id: "copy" }Repeat the template, filling nothing. Excel's Copy Cells.
ReadonlyDateDays: { filler: Date; id: "date.days" }Day by day.
ReadonlyDateMonthEnd: { filler: Date; id: "date.monthEnd" }Month by month, landing on the last day of each.
ReadonlyDateMonths: { filler: Date; id: "date.months" }Month by month, keeping the day where the month is long enough.
ReadonlyDateWeekdays: { filler: Date; id: "date.weekdays" }Business day by business day, skipping weekends.
ReadonlyDateYears: { filler: Date; id: "date.years" }Year by year.
ReadonlyGrowth: { filler: Growth; id: "growth" }A geometric series — the step is a ratio.
ReadonlyGrowthTrend: { filler: Growth; id: "growth.trend"; minValues: 2; options: { trend: true } }A geometric series fitted to the template — the same fit, run on the logs.
ReadonlyLinear: { filler: Linear; id: "linear" }A straight numeric series.
ReadonlyLinearTrend: { filler: Linear; id: "linear.trend"; minValues: 2; options: { trend: true } }A straight numeric series FITTED to the template rather than stepped from it.
A fit needs two points, which is why Excel greys Linear Trend on a single cell and offers
Fill Days there. The arity belongs to the option, not to Types.Linear, which fills
a single value happily enough without it.
ReadonlySeries: { filler: Composite<any>; id: "series" }Read the series off the template. Excel's Fill Series / the Series dialog's AutoFill.
These are IAutoFill.Presets, not fillers: the same filler appears under several of them with different options. Ids are stable and are what a menu entry, a script, or a transaction's operation params name; display labels are localized against the id.
Which of these to show for a given selection is canApply.
The fills that can be OFFERED to a user — the entries of a fill menu or a Series type list.