Relational Operators in Lua

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Following table shows all the relational operators supported by Lua language. Assume variable A holds 10 and variable B holds 20 then:

OperatorDescriptionExample
== Checks if the values of two operands are equal or not, if yes then condition becomes true. (A == B) is not true.
~= Checks if the values of two operands are equal or not, if values are not equal then condition becomes true. (A ~= B) is true.
> Checks if the value of left operand is greater than the value of right operand, if yes then condition becomes true. (A > B) is not true.
< Checks if the value of left operand is less than the value of right operand, if yes then condition becomes true. (A < B) is true.
>= Checks if the value of left operand is greater than or equal to the value of right operand, if yes then condition becomes true. (A >= B) is not true.
<= Checks if the value of left operand is less than or equal to the value of right operand, if yes then condition becomes true. (A <= B) is true.

Example

Try the following example to understand all the relational operators available in Lua programming language:

a = 21
b = 10

if( a == b )
then
   print("Line 1 - a is equal to b" )
else
   print("Line 1 - a is not equal to b" )
end

if( a ~= b )
then
   print("Line 2 - a is not equal to b" )
else
   print("Line 2 - a is equal to b" )
end

if ( a < b )
then
   print("Line 3 - a is less than b" )
else
   print("Line 3 - a is not less than b" )
end

if ( a > b ) 
then
   print("Line 4 - a is greater than b" )
else
   print("Line 5 - a is not greater than b" )
end

-- Lets change value of a and b
a = 5
b = 20
if ( a <= b ) 
then
   print("Line 5 - a is either less than or equal to  b" )
end

if ( b >= a ) 
then
   print("Line 6 - b is either greater than  or equal to b" )
end

When you build and execute the above program it produces the following result:

Line 1 - a is not equal to b
Line 2 - a is not equal to b
Line 3 - a is not less than b
Line 4 - a is greater than b
Line 5 - a is either less than or equal to  b
Line 6 - b is either greater than  or equal to b


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