Python with a twist of R syntax
Are you an R programmer and trying python and don't like the syntax?
Are you tired of fighting against indentation? do you miss curly braces? Do you miss the <- operator to do variable assignment?
Then try pytwister and put a twist of R in your python scripts!
Disclaimer: The package works! but it is meant only as a joke and not to be used on anything serious.
Clone or download the repo and do:
pip install .
Start your python script with the comment # coding=pytwister
(it has to be in the first or second line). Then write your script with
normal python or pytwister R syntax and then execute it.
For example, write an example.py script that contains:
# coding=pytwister
a <- 1
print(a)and execute it:
python example.py
this will print:
1
-
any python code is still valid
-
"<-" assign operator: it will be replaced by a python "=". There should be no space between < and - . If you would like to do a less than comparator to a negative number, do < - (notice the space between < and -),for example 5 < -6 , or use parenthesis like 5 < (-6).
example:
a <- 1
- braces: you can use braces instead of indentation.
example:
for x in range(5){
print(x)
}
In order to disambiguate to the braces to build dictionaries, the opening brace should always be in the same line as the statement and before the newline, otherwise it will be interpreted as dictionary. The closing brace should be alone in its own line.
- "function_name <- function(args)": this will be replace by "def function_name(args)".
example:
myfun <- function(a,b){
return a+b
}
It works only when running scripts, does not work from the interactive console.
Only python 3 is supported.
Pytwister uses support for specifying source code encodings as described in PEP 263. The functionality was originally provided so that python developers could write code in non-ascii languages (eg. chinese variable names). Pytwister creates a custom encoding called pytwister which converts the R syntax elements into regular python before the file is compiled. Once the pytwister codec is registered, any file starting with #coding: pytwister is run through the pytwister parser before compilation.
This package is inspired by interpy and pyxl
Functional languages such as Lisp have macros that capture non executed (quoted) code for the user to modify it. In this way new syntactic elements can be introduced into the language.
I just wanted to explore to what extend python supports this kind of metaprogramming, as it clearly does not support macros.
There are several alternatives to get what lisp macros can do. For example dplyr like pipes have been introduced with a combination of decorators and custom definition of operators in classes (see dfply). Compiled code can be modified using decorators (see python-goto.
These methods however are limited to valid python code. If non-valid python syntatic elements should be added, the only option is to parse the script and replace with valid python syntax before compile. This package is an example on this. Other interesting examples that use different mechanisms are bython and of course hy the later implementing a full lisp interpreter on top of the python virtual machine.