For those interested in financial programming with F#, there's a very nice blog series on "Discount/Zero Curve Construction in F#" over on lesscode.net.
Part 1, Part 2 (Rolling Dates), Part 3 (Bootstrapping), Part 4 (Core Math)
There code is now also available as one snippet on the F# Snippets site, where you can inspect its types, and you can even load the code into Try F# (you have to hit "Run").
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