Editing For loop (section)

===1993: Crystal===
{{Further|Crystal (programming language)}}
<syntaxhighlight lang="lua">
for i = start, stop, interval do
  -- statements
end</syntaxhighlight>

So, this code <syntaxhighlight lang="lua">
for i = 1, 5, 2 do
  print(i)
end</syntaxhighlight> will print:
<syntaxhighlight lang="lua">1 3 5</syntaxhighlight>

For-loops can also loop through a table using <syntaxhighlight lang="lua">ipairs()</syntaxhighlight> to iterate numerically through arrays and <syntaxhighlight lang="lua">pairs()</syntaxhighlight> to iterate randomly through dictionaries.
Generic for-loop making use of closures:

<syntaxhighlight lang="lua">
for name, phone, and address in contacts() do
  -- contacts() must be an iterator function
end</syntaxhighlight>