Raise a warning when a reserved variable is set

[jcassee]

As per a list discussion, it would be nice if a warning was printed if the user tries to set a reserved variable, such as environment.

[mpdehaan]

Classifying this as a bug report so it doesn't get lost in the list.

[samdaltonmaag]

+1, this had me stumped for a bit using "environment", and only figured it out after guessing it might be the case.

[FractalizeR]

Spent several hours figuring out why a variable named environment doesn't contain what I suppose it to contain.

+1 from me.

[FractalizeR]

BTW, is there is a list of all things 'reserved'? Just not to stumble over such cases again...

[bcoca]

not a central one, mostly we have some 'magic' internal vars and then keywords/directives for play, role and task.

[meebey]

I tried to pass a variable named port from a role definition like this:

- { role: myrole, port: '7689' }

The template module didn't like the port variable then like this:

AnsibleUndefinedVariable: ERROR! 'port' is undefined

The port variable was undefined till I renamed it to something else...

[FractalizeR]

@meebey Yep. Very annoying, right? :)

[schnittchen]

I just bumped into this as well, exactly as @meeby did.

While I understand that the devs have more important things to do with currently more than 1k issues open, is there a list of reserved variables names somewhere, maybe a link to the code?

[bcoca]

if only it where that simple, there are many and defined in different places

i added this for the basic objects, but far from a complete list http://docs.ansible.com/ansible/playbooks_directives.html

[schnittchen]

thanks @bcoca!