Added basic implementation for Python code evaluation

2019-11-07 17:18:07 +01:00
parent b818c992ec
commit 448ebc696a
18 changed files with 501 additions and 156 deletions
@@ -226,3 +226,57 @@ need the second call :code:`add("Concepts", "bar")` to produce

 So we are no longer in the usual way of implementing a CRUD.

+
+
+2019-11-06
+**********
+
+Input processing
+"""""""""""""""""
+The basic processing flow should be
+
+::
+
+    1. parsers
+    2. evaluators
+    3. printers
+
+So, for each new input, all known parsers will try to recognize the input. Each parser will
+return a triplet of :code:`(status, concept found (or node found), text message)`
+
+This list of triplet is given to the evaluators. In the same way, there should be multiple
+types of evaluators. There will be the rules that will be introduced later.
+
+All evaluators will provide a list (a guess it will be triplets as well) to the printers.
+
+Python processing
+"""""""""""""""""
+Sheerka natively understand Python. So it will be able to execute Python code.
+I will manage later on the issues caused by the different version of Python, or the fact
+that some external modules must remain isolated (maybe using virtualenv)
+
+My first problem is to correctly implement the :code:`eval / exec` function.
+
+I don't know why, by Python has two similar function to do the same thing. One must use
+eval to evaluate expression, or use exec to execute code. There must be an explanation but,
+as for know, it seems to be a complication for nothing.
+
+The next issue that I will have to tackle is that Sheerka is not a REPL. After the execution
+of the input, the system stops. Nothing is kept in memory (eg RAM).
+The whole idea is to make Sheerka 'remember', even something that happened a long time ago.
+So I should find a way to 'freeze the time'
+
+To better explain what I have in mind. let's say that I want to pretty print an object
+
+.. code-block:: python
+
+    import pprint
+    pp = pprint.PrettyPrinter(indent=4)
+    pp.pprint(stuff)
+
+I need three line in oder to be able to pretty print. I will first try by dumping the
+globals(), using pickle and load it back whenever needed.
+
+If it does not work as expected, I can find a way to save the commands a exec everything
+when needed. (first time, I exec import... second time I exec import + pp == and the last
+time I exec the three statements).