Distinguish generic code_template from specific code_generator

[mccalluc]

• Fix Distinguish generic codegen from the specifics used here #297
• Separate the generic from the specific code generation utilities, and also the corresponding tests. With this change, code_template has no logic that only applies to this project.
• Make the __file__ explicit, since the generic code can be used from different locations.
• Split the notebook and script generation classes. (Java idioms aren't always best, but these classes are big enough to have their own files.)
• Move the analyses into this new directory, so all the templates are near each other.

before:

├── dp_wizard
│   ├── analyses # Top-level directory separated from the other template instances
│   │   ├── histogram
│   │   └── mean
│   └── utils
│       ├── code_generators
│       │   ├── _template.py # Mixes application specific and generic code
└── tests
    └── utils
        ├── test_code_generators.py # Tests are mixed, too

after:

├── dp_wizard
│   └── utils
│       ├── code_generators # ALL of the templates instances, and code to fill the templates
│       │   ├── analyses
│       │   │   ├── histogram
│       │   │   ├── mean
│       │   ├── abc.py # Pull classes out for visibility
│       │   ├── notebook.py
│       │   └── script.py
│       ├── code_template.py # NONE of the template instances specific to this application
└── tests
    └── utils
        ├── test_code_generators.py
        ├── test_code_template.py

[ekraffmiller]

Hi Chuck this looks good, I just had some questions about the naming and reorganization. One more general comment, it might help the code readability to re-name the 'no-tests' folder to something that describes the contents, such as 'template-instances'. Unless the testing code requires the that specific folder name to skip over the files.

[ekraffmiller]

To improve readability, can this file name be changed to code_generator.py?

[mccalluc]

Sure: I'll also add abstract to make that clear.

[ekraffmiller]

I don't understand why this needed to be moved, since it's used specifically for code generation? It seems a little out of place in the generic /utils directory.

[mccalluc]

I want to separate the code_generation with the details of code generation for this particular application, from code_template which is more general, and might eventually be factored out of this repo entirely. The distinction might be most clear looking at the tests.

Perhaps better names would make the distinction more clear, but for now:

• code_generation describes the result, and avoids specifying the implementation. There are different ways you could generate code. For example, you could start from a parse tree instead, but it would still be "code generation"
• code_template is describing the implementation. There are other template libraries, and this works a lot like them, but it is particularly adapted to python code with it's different fill_* methods.

[ekraffmiller]

ok, thanks for the explanation, I see what you mean.

[ekraffmiller]

@mccalluc I think this is ready to merge, after the file name change we discussed. thanks!

[ekraffmiller]

approved