Feature Proposal: New $EMPTY(), $LEFTSTRING(), $RIGHTSTRING(), SUBSTRING(), $INSERTSTRING() functions to SpreadSheetPlugin

Motivation

It is essential that we eliminate excused for not crossing over from (tm)wiki and upgrade to Foswiki

Description and Documentation

Implement to the exact spec what has been add in TWikibug:Item6222

New $EMPTY(), $LEFTSTRING(), $RIGHTSTRING(), SUBSTRING(), $INSERTSTRING() functions to SpreadSheetPlugin

Examples

Impact

Enables easy upgrade and gives us nice new features as well.

WhatDoesItAffect:

%WHATDOESITAFFECT%

edit

Implementation

The plan is to take the spec 100% from the old project

The code will be audited for security but I plan to keep the same model as used throughout the plugin already.

The target is a release of the plugin when implemented so people can upgrade. And the code will be in 1.1.0 and if we ever release a 1.0.5 also there because this enhancement hits T4.3 so we need people to be able to upgrade. The SSP is very used everywhere and it will take seconds after the feature is available in the old project before people use it. So it is urgent to keep up in this case. The enhancement is very contained. The SSP functions are code wise totally separated so there is very little risk that adding this goofs any old function.

-- Contributors: KennethLavrsen - 26 Mar 2009

Discussion

note to test pos=0 case (i think with the latest change in spec, this will now make sense). perhaps also document the 0 case explicitly.

-- WillNorris - 27 Mar 2009