For Python and some other languages, this is the start of the file.
For other languages, this is a special function name reserved for this purpose - generally, “main”.
In the first kind of language, the thought process is basically: I have the flow of execution, starting at the top of the file. If I want to make a library, I should build the things I want to build, then get out of the way.
In the other kind of language, the thought process is basically: I am building a library. If I want to make an executable, I should create an entry point they the execution starts at.
Python doesn’t need the name main check to function at all. that’s just a convenience feature that lets developers also include arbitrary entry points into modules that are part of a library and expected to be used as such. If you’re writing a script, a file with a single line in it reading print("hello world") will work fine when run: python thescript.py
In the first kind of language, the thought process is basically: I have the flow of execution, starting at the top of the file. If I want to make a library, I should build the things I want to build, then get out of the way.
Note the “I have the flow of execution”, and the “if I want to build a library”.
If you just want to build an executable, do as you wish, you already have the flow of execution.
If you want to build a library, make the relevant classes and functions and get out of the way (i.e., no IO, no long-running tasks).
If you want to combine them, use the main name check - or, make a package and do entry points that way. Either way works, because both can fulfill the goal of staying out of the way of those importing this as a library.
All code needs to have an entry point.
For Python and some other languages, this is the start of the file.
For other languages, this is a special function name reserved for this purpose - generally, “main”.
In the first kind of language, the thought process is basically: I have the flow of execution, starting at the top of the file. If I want to make a library, I should build the things I want to build, then get out of the way.
In the other kind of language, the thought process is basically: I am building a library. If I want to make an executable, I should create an entry point they the execution starts at.
The debate is honestly pretty dumb.
Python doesn’t need the name main check to function at all. that’s just a convenience feature that lets developers also include arbitrary entry points into modules that are part of a library and expected to be used as such. If you’re writing a script, a file with a single line in it reading
print("hello world")will work fine when run:python thescript.pyYes, because
Note the “I have the flow of execution”, and the “if I want to build a library”.
If you just want to build an executable, do as you wish, you already have the flow of execution.
If you want to build a library, make the relevant classes and functions and get out of the way (i.e., no IO, no long-running tasks).
If you want to combine them, use the main name check - or, make a package and do entry points that way. Either way works, because both can fulfill the goal of staying out of the way of those importing this as a library.