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Litt's Lua Laboratory:
Lua Hello World
(With Snippets)

Here's a Lua hello world:

#!/usr/bin/lua 
print("Hello World")

The first line tells Linux to run this program with /usr/bin/lua. The second line tells it to print "Hello World". Save the program as "hello.lua", use chmod to make it executable, and run it. Here's the program's output:

slitt@mydesk:~$ ./test.lua
Hello World
slitt@mydesk:~$

Now let's add a couple more lines:

#!/usr/bin/lua 
print("Hello World")
print("Hello World yourself")
print("Howdy")

Run it and it looks like this:

slitt@mydesk:~$ ./hello.lua
Hello World
Hello World yourself
Howdy
slitt@mydesk:~$

Just what you'd expect. Now let's explore comments in Lua. There's a "to end of line" comment, and "between these" comment. The "to end of line" comment is a double hyphen, as shown to add a comment to the end of the first line and comment out the second line:


#!/usr/bin/lua 
print("Hello World")          --This is the first line
-- print("Hello World yourself")
print("Howdy")

Run it and you get just what you expect:

slitt@mydesk:~$ ./hello.lua
Hello World
Howdy
slitt@mydesk:~$

Now let's remove those comments and comment out the first two lines with an inclusive comment:

#!/usr/bin/lua 
--[[print("Hello World")
print("Hello World yourself") ]]
print("Howdy")

As you can see, everything between --[[ and ]] is commented out. That's the way you inclusively comment out. It's often used to comment out large blocks of code. Typically per-line comments are used to actually comment things. Here's the result of the preceding code:

slitt@mydesk:~$ ./test.lua
Howdy
slitt@mydesk:~$

Just as expected. Now you know how to write a simple Lua program.

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Troubleshooters.Com and Code Corner Present

Litt's Lua Laboratory: Lua Hello World (With Snippets)

Litt's Lua Laboratory:
Lua Hello World
(With Snippets)