WHATIF_PACKAGE

const WHATIF_PACKAGE: IEnginePackage;

Defined in: packages/engine/src/packages/whatif/WhatIfPackage.ts:47

What-if and sweeps, re-running a line with different inputs (GitHub issue #505).

line 4 with deposit = 150000 reads as “what line 4 would say if deposit were 150000”, and line 4 for rate from 3% to 6% step 1% as “line 4’s answer for each of those rates”. Neither edits the note. Both re-run every line from the top of the document to the target, from its text, in a scratch engine with the input held fixed, so the input reaches the target through every line between (see LineExecutionContext.rerunLines).

Grammar and work live apart, the split every package here uses:

• whatIfNormalizerRule fuses line N with into WHAT_IF when a <name> = follows, and sweepNormalizerRule fuses line N for <name> from into SWEEP and the sweep’s step into SWEEP_STEP. Neither with, for nor step becomes a keyword anywhere else.
• WhatIfParselet and SweepParselet read the rest and emit the plugin calls.
• WhatIfPluginFunctions does the work, including the sweep’s step and work limits.

Named scenarios (#744) are a what-if with a name kept in the note: scenario bull with growth = 8% declares one, and line 5 under bull reads line 5 with its inputs, through the same re-run.

Registered after LINES_PACKAGE, whose rule mints the LINE_REF both of this package’s rules read.