[somat]

The thing that surprised me was that you can't write an interpreter in an interpreted language, at least not in obsd. It is possible if you jump through a few hoops but you can't directly call it.

An example: if you made a language in python /bin/my_lang: #does nothing but pretend it does

    #!/usr/local/bin/python3
    import sys
    print('my_lang args', sys.argv)
    for line in sys.stdin:
      print('invalid_line:', line)

my_script:

    #!/bin/my_lang
    line of stuff
    another line of stuff

    chmod u+x my_script
    ./my_script

Probably for the best, but I was a bit sad that my recursive interpreter scheme was not going to work.

Update: looks like linux does allow nested interpreters, good for them.

https://www.in-ulm.de/~mascheck/various/shebang/#interpreter...

really that whole document is a delightful read.

[jolmg]

Worked for me, but the way you described it has issues:

1. You chmod my_script twice.

2. Did you chmod u+x /bin/my_lang too? Since you put it in /bin, are you sure the owner isn't root?, in which case your user wouldn't have execute permission. Try +x instead of u+x.

3. Do you have python in that path? Try `/usr/bin/env python` instead.

4. In case you expected otherwise, my_script wouldn't be passed through stdin. It's just provided as an argument to my_lang.

[somat]

I am on openbsd. which does not allow it, it looks like nested interpreters are s supported on linux. So my loss there.

[teo_zero]

Wait... your interpreter reads from stdin. Shouldn't it read its first arg, instead?

[mbreese]

IIRC interpreters can also read their programs from stdin. Try piping a script to bash and see if it works.

(Actually, this is how the `curl install.sh | bash` anti pattern works. )

[teo_zero]

Independently of what the interpreter can do, it's #! that doesn't pass the file to it.

[somat]

I think that was what I was trying to figure out, how the program was passed. but OpenBSD does not do nested interpreters, it looks like if I had tried Linux it would have worked.