User:Anaminus/return nutshell

"return" in a nutshell....

The return statement is used to return values from a function.

Example:

function number() 
return 7 
end 

print(number())

'7' will print in the output.

More Examples:

Variables can be used to return values,

function string() 
local s = "Message" 
return s 
end

print(string())

'Message' will print in the output.

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When assigning a function to a variable, the variable becomes what the function returns.

function number() 
return 11 
end 

n = number() 

print(n)

'11' will print in the output.

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'return' acts as output.

function add(value) 
v = value + 10 
return v 
end 

n = add(5) 

print(n)

'15' will print in the output.

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Another output example:

function add(value) 
return value + 10 
end 

n = add(6) 

print(n)

'16' will print in the output.

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'return'ing nothing returns nil

function nothing() 
return 
end 

n = nothing() 

print(n)

'nil' will print in the output.

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'return'ing nothing is often used to escape a function

When not escaping:

function DontEscape(value) 
if value == 0 then 
print("it was 0") 
end 
print("the end") 
end 

DontEscape(1)

'the end' will print in the output.

DontEscape(0)

'it was 0' will print in the output.

'the end' will print in the output.

When escaping:

function Escape(value) 
if value == 0 then 
print("it was 0") 
return 
end 
print("the end") 
end 

Escape(1)

'the end' will print in the output.

Escape(0)

'it was 0' will print in the output.

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'return' can be used to return multiple values.

function NotMultiple() 
return 10 
return 20 
end 

print(NotMultiple())

'10' will print in the output.

function Multiple() 
return 10,20 
end 

print(Multiple())

'10 20' will print in the output.

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Multiple variables can be set with multiple returns.

Normal:

a,b,c = 5,6,7 

print(a) 
print(b) 
print(c)

'5' will print in the output.

'6' will print in the output.

'7' will print in the output.

Multiple:

function multiple() 
return 15,16,17 
end 

a,b,c = multiple() 

print(a) 
print(b) 
print(c)

'15' will print in the output.

'16' will print in the output.

'17' will print in the output.

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