C Preprocessor Macro equivalent for Python
I use to define macros (not just constants) in C like
#define loop(i,a,b) for(i=a; i<b; ++i)
#define long_f(a,b,c) (a*0.123 + a*b*5.6 - 0.235*c + 7.23*c - 5*a*a + 1.5)
Is there a way of doing this in python using a preprocess instead of a function?
*By preprocess I mean something that replaces the occurrences of the definition before running the code (actually not the whole code but the rest of the code, because since it's part of the code, I guess it will replace everything during runtime).
If there is, worth it? Will there be a significant difference in run time?
Answer
Is there a way? Yes. There's always a way. Should you do it? Probably not.
Just define a function that does what you want. If you are just concerned about code getting really long and want a one-liner, you can use a lambda function.
long_f = lambda a,b,c: a*0.123 + a*b*5.6 - 0.235*c + 7.23*c - 5*a*a + 1.5
long_f(1,2,3) == 28.808
And of course your first example is already way prettier in Python.
for i in range(a,b):
...
Edit: for completeness, I should answer the question as asked. If you ABSOLUTELY MUST preproccess your Python code, you can use any programming language designed for templating things like web pages. For example, I've heard of PHP being used for preprocessing code. Instead of HTML, you write your code. When you want something preprocessesed, you do your PHP blocks.