bas55 [1] is the closest I can find to a Dartmouth style basic (so 70s rather than 80s). Alas constants are truncated at 6 places (internal calculations are all doubles). It compiles fine and works well complete with LOAD, SAVE and limited line editing.
Does anyone know of a portable basic interpreter that supports double precision all through?
The kind of stuff I (used to) do [2] requires more than 6 figures.