Comparison of while and until loops
Conditionals and loops example from a Well House Consultants training course
More on Conditionals and loops [link]
Source code: wcd Module: U103
amount = 10
--[[ Until v while
Loop runs at least once
Check at end of loop
Carries on until condition is TRUE
Loop runs at least zero times ;-)
Check at start of loop
Carries on until condition is FALSE
print ("What's the exchange rate?")
erate = io.read() + 0
until erate > 0.0
print ("What's the increment")
stepper = io.read()
-- erate = 2.04
while amount <= 100 do
dollars = amount * erate
print ("pounds " .. amount , " dollars " ..
amount = amount + stepper
--[[ -------- Sample Output -------------
[trainee@easterton al]$ lua wcd
What's the exchange rate?
What's the increment
pounds 10 dollars 12.5
pounds 15 dollars 18.75
pounds 20 dollars 25
pounds 25 dollars 31.25
pounds 30 dollars 37.5
pounds 35 dollars 43.75
pounds 40 dollars 50
pounds 45 dollars 56.25
pounds 50 dollars 62.5
pounds 55 dollars 68.75
pounds 60 dollars 75
pounds 65 dollars 81.25
pounds 70 dollars 87.5
pounds 75 dollars 93.75
pounds 80 dollars 100
pounds 85 dollars 106.25
pounds 90 dollars 112.5
pounds 95 dollars 118.75
pounds 100 dollars 125
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