This repository contains a preemptive type checking implementation for a subset of the cpython 3.3, Python programming language implementation.
This is a novel type checking mechanism, based on years of research at the University of Southampton. At the core of this mechanism is a type inference system that identifies potential type errors through a flow- sensitive static analysis. This analysis is invoked at a very late stage, after the compilation to bytecode and initialisation of the program. It computes for every expression the variable's present (from the values that it has last been assigned) and future (with which it is used in the further program execution) types, respectively. Using this information, our mechanism inserts type checks at strategic points in the original program, thus preemptive type errors at an early stage.
Simply import the library into your program, to start using preemptive type checking, instead of dynamic typing, as follows:
from typer import Analyser
def main():
# Python, with some restricted features
.
if __name__=='__main__':
# Full Python language up to here.
# We first analyse the function initialised above.
a=Analyser(main)
# We transform the function such that it
# implements preemptive type checking semantics.
a.emit()
# We call the transformed function.
_main()Written by: Neville Grech
For more information about preemptive type checking read my PhD thesis
If you would like to contact me, email me at nevillegrech at gmail.