Difference between revisions of "Basic lua: Operators"

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Lua operators are expressions used to perform calculations or to pass arguments between different value types. __NOTOC__
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Lua operators are expressions used to perform calculations or to pass arguments between different value types.
 
<div class="ftoc">__TOC__</div>
 
<div class="ftoc">__TOC__</div>
 
== Conditional Operators ==
 
== Conditional Operators ==

Revision as of 17:34, 20 August 2014

Lua operators are expressions used to perform calculations or to pass arguments between different value types.

Conditional Operators

if Query if something does or does not meet a certain condition.
else Do something else if the query condition was not met.
elseif Used to add additional if queries, if the initial query condition was not met.
end This is used to close various queries or functions; there must be the same amount of end as if; except in instances where elseif has been used.
Example 1: if condition is true (method 1)
local a = true

if a then
 print("a = true")
end
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Example 2: if condition is true (method 2)
local a = true

if a == true then
 print("a = true")
end
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Example 3: if condition is false
local a = false

if a == false then
 print("a = false")
end
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Example 4: if condition is not met, then do else
local a = false

if a then
 print("a = true")
else
 print("a = false")
end
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Example 5: if condition is not met, then do elseif
local a = false

if a then
 print("a = true")
elseif not a then
 print("a = false")
end
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Logical Operators

and Allows you to check multiple conditions in a single if query.
or Allows you to add an alternative if query into a single if query.
not Checks if condition equals false or negative.
Example 1: if condition a is true and condition b is false then
local a = true
local b = false

if a == true and b == false then
 print("a = true", "b=false")
end
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Example 2: if condition is true or condition == true then
local a = true

if a or a == true then
 print("a = true")
end
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Example 3: if condition is not true
local a = false

if not a then
 print("a = false")
end
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Comparison Operators

== Equal to.
~= Does not equal.
>= Greater than or equal to.
> Greater than.
<= Less than or equal to.
< Less than.
Example 1: if a equals 1
local a = 1

if a == 1 then
 print("a = 1")
end
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Example 2: if a does not equal 2
local a = 1

if a ~= 2 then
 print("a = " .. a)
end
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Example 3: if a is greater than or equal to 2
local a = 5

if a >= 2 then
 print("a = " .. a)
end
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Example 4: if a is greater than 2
local a = 3

if a > 2 then
 print("a = " .. a)
end
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Example 5: if a less than or equal to 2
local a = 2

if a <=  2 then
 print("a = " .. a)
end
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Example 6: if a less than 2
local a = 0

if a <  2 then
 print("a = " .. a)
end
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