exchange rate example as a function

Functions. example from a Well House Consultants training course
More on Functions. [link]

Source code: exrate Module: U106

--[[
There's often a requirement to reuse a
piece of code ... and a function is a
good way to do that.

In Lua, functions are "first class"
variables, and so can be assiged,
redefined and have lots of other things
done to them ... not all of which are
good practise mosty of the time
]]

function ert(rate, hmc)
for amount= 10,100,10 do
        exd = amount * rate
        change = exd - hmc
        if change < 0 then
                print (amount, exd, "Have some chicken instead")
        else
                print (amount, exd, " You can buy it and get ",
                        change, "change")
        end
end
end

amazing = ert

meatcost = io.read()

ert(1.25,meatcost)
amazing(1.657,63.4)

print (meatcost)

--[[
[trainee@easterton gwh]$ lua exrate
56
10 12.5 Have some chicken instead
20 25 Have some chicken instead
30 37.5 Have some chicken instead
40 50 Have some chicken instead
50 62.5 You can buy it and get 6.5 change
60 75 You can buy it and get 19 change
70 87.5 You can buy it and get 31.5 change
80 100 You can buy it and get 44 change
90 112.5 You can buy it and get 56.5 change
100 125 You can buy it and get 69 change
10 16.57 Have some chicken instead
20 33.14 Have some chicken instead
30 49.71 Have some chicken instead
40 66.28 You can buy it and get 2.88 change
50 82.85 You can buy it and get 19.45 change
60 99.42 You can buy it and get 36.02 change
70 115.99 You can buy it and get 52.59 change
80 132.56 You can buy it and get 69.16 change
90 149.13 You can buy it and get 85.73 change
100 165.7 You can buy it and get 102.3 change
56
[trainee@easterton gwh]$
]]

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