Track cell type better

[wojciechczerniak]

Description

Currently, after calculations that are including date and time, we have no way to figure out how we should format the final output. We will get number as a value. This hides the meaning from the end-user. Most of the spreadsheet apps are tracking the operations and can format the value correctly. We can format the value on display, but we need the information about the value type. Current CellType returned by the public API method is limited:

hyperformula/src/Cell.ts

Lines 60 to 66 in 1f11e07

	export enum CellValueType {
	EMPTY = 'EMPTY',
	NUMBER = 'NUMBER',
	STRING = 'STRING',
	BOOLEAN = 'BOOLEAN',
	ERROR = 'ERROR',
	}

Date, Time and DateTime Logic

We can use this source [1] as a reference how to handle ops. But we should compare it with other spreadsheet apps

Functions

Some functions are more or less easy: =DATE() returns a date.

Links

[1] https://help.libreoffice.org/6.4/en-US/text/shared/01/05020301.html

[wojciechczerniak]

At today's meeting with @krzysztofspilka and @bardek8 we've decided that this feature has to wait for more use case scenarios. ATM it's considered a niche and we will focus on other features.

Moving to Backlog.

[wojciechczerniak]

Done in #590