Lua Programming/comment

Comments are pieces of text or whitespace that can be included in a program to make the code more understandable to a programmer. Comments have no effect on the running program and are ignored by the lua interpreter.

Comments start with a doublehyphen
In lua, comments start with a doublehyphen and run until the end of the line:

-- This is a comment print "Hello World!"

Block comments
Block comments start with doubleshovel and run until doubleclosebox:

--Comments can be spread across several lines print "Hello World!"

Enabled code within comments
By adding a hyphen to a doubleshovel to form a long handled doubleshovel, this enables code within the comment to become enabled, rather than commented out:

---The long handled doubleshovel means that this code will run print "This will print because it is not a comment!" -- We can still include comments by prefixing them with a doubledash -- print "This will not print because it is commented out"

Nested comments
A limitation of block style comments is that it is not possible to nest existing code containing comments without stripping the doubleshovel and doubleclosebox symbols from the nested code:

--  This will not work. Nesting of comment blocks will cause a syntax error.   --[[     By nesting existing code containing a comment, a syntax error will occur. This is because the nested symbols will confuse the interpreter, so a modification is required to remove the symbols      print "Hello" ]]

The code needs modification as follows:

--  The nested comment block markers have been removed   @ This existing comment has had its block markers removed to prevent a syntax error   @   print "Hello"