FPSheet
A Spreadsheet program with Haskell as the scripting language
The prototype was written in C, it can be tried out in the c-prototype branch. I am currently rewriting the tool in Haskell, which I am doing in this master branch.
FPSheet is a spreadsheet program, where the scripting language for computing cell's values from formulas runs Haskell internally. This arguably provides a more uniform experience than what is provided by the scripting languages of standard spreadsheet programs. Note: this README currently assumes some familiarity from the reader with ghc's ghci tool.
Currently the tool starts a ghci session in the background. When a cell is defined or edited, a unique variable is defined or redefined inside this ghci session. For example, if cell abd124 is edited to: "45", FPSheet sends the following to the ghci session: "let abd124 = 45". Similarly, if cell a4 is edited to: "a5 * 10", FPSheet sends the following to the ghci session: "let a4 = a5 * 10".
Interestingly, since Haskell is lazily evaluated, and since Haskell regards function values as first class citizens, any custom function can be defined inside a cell. Any other cell can then apply this function simply by referring to the cell.
Installation
Run: stack install
Usage
Run: stack exec FPSheet-exe
The program has vim-like modes:
- normal mode for moving around
- edit mode for editing the definition of a cell
While in normal mode, press:
:qto exit.:w <filename>to write the sheet to disk:r <filename>to read a sheet from disk:i <filename>to import an .xlsx file (imports from cell values):I <filename>to import an .xlsx file (imports from cell formulas if set, falls back to cell values for cells that do not have a formula definition set):<column><row>to jump tocolumn,row(e.g.a10,azzz4050, etc.)<ESCAPE>to interrupt the ghci backend (useful for when you accidentally defined a cell that cannot finish evaluation)
TODOs
- Figure out a way to get something like [a1..a4] to evaluate to [a1,a2,a3,a4]
- Copy pasting cells (properly handling loose and stuck cell references)
- Exporting to excell savefiles
- Undo & redo
- Many many more vital features (aka: TODO: write these out)
