On Thu, Jun 13, 2019 at 1:02 AM Andre Roberge email@example.com wrote:
On Wed, Jun 12, 2019 at 7:56 PM Yanghao Hua firstname.lastname@example.org wrote:
On Wed, Jun 12, 2019 at 11:27 PM Chris Angelico email@example.com wrote:
Yes, you would need some sort of syntactic parser. There are a couple of ways to go about it. One is to make use of Python's own tools, like the ast module; the other is to mandate that your specific syntax be "tidier" than the rest of the Python code, which would permit you to use a more naive and simplistic parser (even a regex).
Yep ... I just tried to use MacroPy3 to handle this but failed, seems MacroPy3 does expect valid Python syntax in the first place for anything else to happen. I also tried the raw ast module which seems also the case. So it means if one want to use python ast module to parse user input, the user input has to be valid python syntax (e.g. no <==) at the first place. Seems this is a chicken-egg problem.
As I mentioned very early on in this seemingly-never-ending discussion, there is a way to do things similar to what you want to do, by doing transformations on the source code prior to execution (prior to constructing an AST).
Here's the link to the set of examples which I have done as demonstrations of this technique: https://github.com/aroberge/experimental/tree/master/experimental/transforme...
I think your readme file self explains why already, I do have a solution (multiple solution actually), this is the quest for the final miles to make it look concise, intuitive and ***easy to implement***.
Given two mathematical terms or expressions a and b, they can occur:
- on a single line - immediately following an assert keyword - immediately following an if keyword
However, in the current implementation, anything else will fail.