Re: [Feature request]: analogous to --- if __name__ == “__main__”: ---- of python in lua modules

[Dirk Laurie <dirk.laurie@...>]

2014-09-21 4:45 GMT+02:00 Ashish Ranjan <ashishwave@yahoo.com>:
> FEATURE REQUEST: In python , we have a construct
>         if __name__ == “__main__”:
> so that if a module .lua file is executed by itself then this code block
> executes, but if this module is imported(required() as in lua) by other
> script file, then this code blosk is not executed.
> Can we have this construct in lua. This will be an important step in life of
> a lua module.
>
> Kindly see for better explanation http://stackoverflow.com/a/20158605

Before I get to your topic, please note that your mail configuration
produces an X-Spam score of 7.2 which is likely to trigger the Spam
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There are many ways to test something of the kind. None of them
does exactly what you want, since Lua does not have __name__,
but maybe some of them could answer you purpose.

One rather easy-to-understand way is to test debug.traceback().
I've made a file ./snoopy.lua containing one line:
   print(debug.traceback())

I get the following output:

$ lua ./snoopy.lua
stack traceback:
    ./snoopy.lua:1: in main chunk
    [C]: in ?
$ lua -e "require 'snoopy'"
stack traceback:
    ./snoopy.lua:1: in main chunk
    [C]: in function 'require'
    (command line):1: in main chunk
    [C]: in ?
$ lua -e "dofile 'snoopy.lua'"
stack traceback:
    snoopy.lua:1: in main chunk
    [C]: in function 'dofile'
    (command line):1: in main chunk
    [C]: in ?

They're different, allowing you to test inside 'snoopy.lua'.