[Richard Suchenwirth] - The following routine is not interesting for its
algorithm. Two days after the introduction of Euro cash, this little Euro calculator rather commits the variety of soon extinct European currencies, and their fixed exchange rates, to history (and Tcl code):

 proc Euro {direction currency amount} {
    set usage "usage: Euro {from|to} currency amount"
    switch -- $currency {
        ATS - �S   {set f 13.7603}
        BEF - bfr  {set f 40.3399}
        DEM - DM   {set f 1.95583}
        ESP - Ptas {set f 166.386}
        FIM - Fmk  {set f 5.94573}
        FRF - FF   {set f 5.55957}
        GRD - Dr   {set f 340.750}
        IEP        {set f .787564}
        ITL - Lit  {set f 1936.27}
        LUF - lfr  {set f 40.3399}
        NLG - hfl - f {set f 2.20371}
        PTE - Esc  {set f 200.482}
        default    {error "bad currency $currency - $usage"}
    }
    switch -- $direction {
        from    {set result [expr {$amount/$f}]}
        to      {set result [expr {$amount*$f}]}
        default {error "bad direction $direction - $usage"}
    }
    format %.2f $result
 }
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[Arjen Markus] As a Dutchman, I do like the use of the symbol "f", as this is the now all but extinct Dutch currency symbol :-) (To those with an interest in history: the "f" comes from "florin", a name derived from the wonderful city of Florence, Italy. In fact, an old name for the Dutch guilder is "florijn". Alas, those bygone days ...)
[RS] Added "f" as alias for NLG. (I picked the variable name "f" as abbrev for "factor", but glad you like it ;-)
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