Lua Comments and Variables
Numbers and the Math library. example from a Well House Consultants training course
More on Numbers and the Math library. [link]
Source code: vars.lua Module: U102
-- Comments - from "--" to the end of line OR
--[[ from <<< that string you see at the left
over as many lines as you like and so on until ]]
-- Variables in Lua
Variables in Lua start with a letter and comprise letters
digits and underscores. They ARE case sensitive and must
not be the languages's keywords or reserved words -
and break do else elseif end false for function if in
local nil not or repeat return then true until while ]]
-- Assignment with "=" sign.
-- Lines end at a new line character
-- Variables typed and created on the fly
a = 1
beef_tea = "Old fashioned"
-- Variables are re-typed as need be
-- If you refer to a variable that does not exist, it's nil
-- usual maths operators and rule apply
A="John the Swan and Henry the Hippo"
c = (a + a) * b + b * b
-- That's 1 + 1, times 3 (6 so far)
-- plus 3 times 3 (9) giving a result of 15
-- Divisions float, even if inputs are both integer
-- You can write hex integers too ...
v = 5/3
w = 5/3.0
x = 0x16/4
--[[ ---------------------------- Sample Output ------------
[trainee@easterton u102]$ lua vars.lua
1 2 3 Old fashioned
John the Swan and Henry the Hippo nil 15 nil
1.6666666666667 1.6666666666667 5.5
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