Editing Variadic function (section)

=== In [[Lua (programming language)|Lua]] ===
[[Lua (programming language)|Lua]] functions may pass varargs to other functions the same way as other values using the {{Code|return}} keyword. tables can be passed into variadic functions by using, in Lua version 5.2 or higher<ref>{{Cite web |title=Lua 5.2 Reference Manual |url=https://www.lua.org/manual/5.2/manual.html#pdf-table.unpack |access-date=2023-02-05 |website=www.lua.org}}</ref> {{Code|table.unpack}}, or Lua 5.1 or lower<ref>{{Cite web |title=Lua 5.1 Reference Manual |url=https://www.lua.org/manual/5.1/manual.html#pdf-unpack |access-date=2023-02-05 |website=www.lua.org}}</ref> {{Code|unpack}}. Varargs can be used as a table by constructing a table with the vararg as a value.<syntaxhighlight lang="lua">
function sum(...) --... designates varargs
   local sum=0
   for _,v in pairs({...}) do --creating a table with a varargs is the same as creating one with standard values
      sum=sum+v
   end
   return sum
end

values={1,2,3,4}
sum(5,table.unpack(values)) --returns 15. table.unpack should go after any other arguments, otherwise not all values will be passed into the function.

function add5(...)
  return ...+5 --this is incorrect usage of varargs, and will only return the first value provided
end

entries={}
function process_entries()
   local processed={}
   for i,v in pairs(entries) do
      processed[i]=v --placeholder processing code
   end
   return table.unpack(processed) --returns all entries in a way that can be used as a vararg
end

print(process_entries()) --the print function takes all varargs and writes them to stdout separated by newlines
</syntaxhighlight>