Distribution layout

• For development / standalone version TDL_DIR is the local src path (e.g. ~/code/tdl) and SCRIPT_DIR is TDL_DIR

• For site packages version (installed via TDL_DIR/setup.py), TDL_DIR is python/.../site-packages/tdl and SCRIPT_DIR is python/bin/tdl.

• In either case the users 'path' should include the directory with the 'tdl' script and python executable.

  SCRIPT_DIR/tdl	startup script
  TDL_DIR/tdl_ast.py	startup script for ast implementation
  TDL_DIR/tdl_pds.py	startup script for pds implementation
  TDL_DIR/setup.py	script for site-packages install
  TDL_DIR/astlib/...	contains ast shell program and associated modules
  TDL_DIR/pds/...	contains pds shell program and associated modules
  TDL_DIR/modules/...	contains add-on/application modules
  TDL_DIR/examples/...	examples
  TDL_DIR/tests/...	tests

Startup script and PYTHONPATH

• The tdl script should take as an argument a keyword to chose which shell to run (ast or pds).
• The tdl_ast.py or tdl_pds.py script then should add the following to sys.path:

  .	current working directory
  TDL_DIR	parent directory (will be on pythonpath already if its in site-packages)
  TDL_DIR/astlib	if ast make sure astlib on path, otherwise exclude it
  TDL_DIR/pds	if pds male sure pds on path, otherwise exclude it
  TDL_DIR/modules/*	add-on modules (recursively add all paths)

Startup options

• In pds shell there is a file pds/startup.pds that is read/executed at startup. This can be used to set local site preferences (e.g. which modules to import on default, default editor etc).

• After initial startup of the interactive shell (both ast and pds) search for a 'HOME' environment variable, and pass HOME/.tdl_init for execution if it exists. This can be used to set user specific options (e.g. load specific modules, change to a default working directory etc.).