while and for loops - Lua example

Conditionals and loops example from a Well House Consultants training course
More on Conditionals and loops [link]

Source code: lloops Module: U103

#!/usr/bin/env lua

--[[

A for loop lets you iterate from a start value to
an end vale with an optional step (first form) or
through a table (second form).

]]

print ("\nwhile loop in lua")
j=14
while j < 20 do
        print (j)
        j = j + 1
end

print ("\ntwo parameter form of for - steps of 1")
for k = 1, 5 do
        print (k)
end

print ("\nthree parameter form of for - step size specified")
for k = 1, 5, 2 do
        print (k)
end

print ("\nthere is no one parameter form of for in lua")

print ("\nfor loop to parse a table with automatic keys")
days = {"Monday","Wednesday","Friday"}
-- ipairs is "INDEXED pairs"
for index,today in ipairs(days) do
        print (index, today)
end

print ("\nfor loop to parse a table with specified keys")
days = {Monday = "Chinese",Wednesday = "Pizza" ,
        Thursday = "The Pub", Tuesday = "Subway",
        Friday = "Fish and Chops"}
-- pairs returns key and value pairs
for index,today in pairs(days) do
        print (index, today)
end

--[[ -------------------- Sample Output

[trainee@easterton u103]$ lua lloops

while loop in lua
14
15
16
17
18
19

two parameter form of for - steps of 1
1
2
3
4
5

three parameter form of for - step size specified
1
3
5

there is no one parameter form of for in lua

for loop to parse a table with automatic keys
1 Monday
2 Wednesday
3 Friday

for loop to parse a table with specified keys
Tuesday Subway
Wednesday Pizza
Friday Fish and Chops
Thursday The Pub
Monday Chinese
[trainee@easterton u103]$

]]

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