Error while converting python variables

[alcino-alves]

hello guys!
I need some help!!!
i've just created a script for setting the project in maya using python and it's not working the way it should.

as u may know, the "setProject" command is only available for mel. i had to convert a python variable (that holds the path to be set) to mel so i could use this variable to complete the command, like this:
"""
dirpath = "C:\Documents and Settings\3d\My Documents\maya\projects\default\scenes"
maya.mel.eval (' $dirpath = python ("dirpath") ')
maya.mel.eval (' setProject $dirpath; ')
"""

when i open up maya, the userSetup.py is loaded normally (and it imports the script)
i call the function and it seems to work coz the interface is loaded and some functions too  like adding a user and removing a user functions. everything is fine so far, but when i try to set the project, it occurs and error right in this line:
"""
    if os.path.isdir(dirpath) == True:
        maya.mel.eval (' $dirpath = python ("dirpath") ') ...
"""
and this is the error:
"""

# Traceback (most recent call last):
#   File "", line 1, in
#   File "W:\TOOLS\SCRIPT\PYTHON\MAYA\setProject.py", line 394, in setProjectFunc
#     maya.mel.eval (' $dirpath = python ("dirpath") ')
# RuntimeError: Error occurred during execution of MEL script #

"""
and i'm almost sure the problem is in this line because when i execute the whole script in the script editor it works!!!
it's a kind of problem that occurs while the variables are being converted i guess.. but i dont understand why it only works when i execute it in the script editor!

does anyone know why it happens? can anyone help me with that?

thanks in advance!

[joojaa]

and i'm almost sure the problem is in this line because when i execute the whole script in the script editor it works!!!
it's a kind of problem that occurs while the variables are being converted i guess.. but i dont understand why it only works when i execute it in the script editor!

You are right, And ill tell you WHY this is. The script editor is global, so whatever you do in python or mel inside the script editor it gets to be global. Your module is not global. And the mel you evaluate is not global it is as if you were typing:

global dirpath
dirpath = "C:\Documents and Settings\3d\My Documents\maya\projects\default\scenes"
maya.mel.eval (' global $dirpath;  $dirpath= python ("dirpath") ')
maya.mel.eval (' setProject $dirpath; ')

Which i must say is a EXTREMELY bad idea!

now then about calling this wouldn't it just be easier to do the following:

dirpath = "C:\Documents and Settings\3d\My Documents\maya\projects\default\scenes"
maya.mel.eval (' setProject '+dirpath )

It would save you a lot of code and 2 times polluting the global namespace.

FYI:

as u may know, the "setProject" command is only available for mel.

Actually it seems you dont know this. As its not a command its a procedure, you can actually do exactly the same thing in python, see if you lookat what the mel command does is is jut basically calls the:

workspace -o $path;

with a lot of safeguards, and gui updates. But you can do this all without the hooks in in python too with:

dirpath = "C:\Documents and Settings\3d\My Documents\maya\projects\default\scenes"
cmds.workspace( dirpath , o=True )

[joojaa]

maya.mel.eval (' setProject '+dirpath )

Oh sorry correction to this

maya.mel.eval (' setProject "'+dirpath+'"' )