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+### Background
+
+This is a (largely abandoned) experiment in building a small "Excel-style" expressions language. The core of the language works, but it only has four keywords implemented (sum, any, all, average).
+
+Example expressions:
+
+```
+sum(8,9)
+sum(8,99,67,average(sum(87,23),8,67))
+any(1,0,0,1,1)
+any(0,2)
+```
+
+The quickest way to try the language is to use the REPL, the (incomplete) API and app were intended to become a way of using the language from the browser.
+
+The web app is a Elm app, which just displays one table at present. The API is more full-featured. The API allows for tables to be created, overwritten, downloaded, to have rows inserted, and allows for expressions to be evaluated with-or-without the context of a table of data.
+
+### Running the Programs
+
+Before starting, ensure cabal is installed and `cabal update` has been run.
+
+To start the REPL: `cabal run repl`
+
+To start the web server: `cabal run hs`
+
+The Elm webapp builds to a single `index.html`, which was been committed to this repo, and needs no further building. However, if you desire, you can download Elm from https://elm-lang.org/, and build the Elm client by doing `cd elm-client && elm make src/Main.elm`.
+
+The REPL can interpret files containing expressions if they are passed in over stdin: `cabal run repl < file-of-expressions`.
+
+### License
+
+Released into the public domain without any guarantee of any fitness for any purpose whatsoever.