How to write an inline-comment in Python

Question

Is there a method of ending single line comments in Python?

Something like

/* This is my comment */ some more code here...

Solution 1

Whitespace in Python is too important to allow any other kind of comment besides the # comment that goes to the end of the line. Take this code:

x = 1
for i in range(10):
             x = x + 1
/* Print. */ print x

Because indentation determines scope, the parser has no good way of knowing the control flow. It can't reasonably eliminate the comment and then execute the code after it. (It also makes the code less readable for humans.) So no inline comments.

Solution 2

No, there are no inline-block comments in Python. But you can place your comment (inline) on the right. That's allows you to use syntax and comments on the same line. Anyway, making comments to the left of your code turn reading difficult, so...

Ex:

x = 1 # My variable

Solution 3

This is pretty hideous, but you can take any text convert it into a string and then take then length of that string then multiply by zero, or turn it into any kind of invalid code. example

history = model.fit_generator(train_generator,steps_per_epoch=8,epochs=15+0*len(", validation_data=validation_generator"), validation_steps=8,verbose=2)

Solution 4

If you're doing something like a sed operation on code and really need to insert plain text without interfering with the rest of the line, you can try something like:

("This is my comment", some more code here...)[1]

Eg.,

my_variable = obsolete_thing + 100

could be transformed with sed -e 's/obsolete_thing/("replacement for &", 1345)[1]/' giving:

my_variable = ("replacement for obsolete_thing", 1234)[1] + 100

Solution 5

You can insert inline comment. Like this

x=1; """ Comment """; x+=1; print(x);

And my python version is "3.6.9"

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Comments

[mgilson]

I'm not sure there is any need to blame this on the parser's sensitivity to whitespace. You could just say that the line starts where the comment starts if you wanted... I think it's more the philosophy that the middle of a line is no place for a comment. :-)

[ABMagil]

The parser isn't the only thing that reads the code... Personally, I would rather read python where lines start where the characters start. It's not a huge deal, but it's the little things that make python easy and fun.

[TheSoundDefense]

@ABMagil that is true... a human parser is probably more error-prone than the actual parser :)

[TheJP]

I agree that comments inline before or after code are "ugly". But it can be very useful to comment out a specific part (inline) while debugging and I'd like to do the following (new lines after each '\'): data_frame \ # .coalesce(1) \ .write \ .option('header', 'true') \ # Comment about csv file format \ .csv(file_name)

[Braden Best]

But what about line continuations? The sequence, \#, raises a SyntaxError because apparently they decided to make whitespace a part of the line continuation token. I can't even move it to the next line because the comment terminates the line continuation. Why? This behavior is nonsensical. The sequence \^J# should just result in an implicit line continuation continuation after the comment terminates, or \# should be allowed, or there needs to be a dumb inline comment that interprets [comment] stuff as just ` stuff`, all consequences included.

[Hamza]

How this relates to the question in any way?

[Roland Pihlakas]

@Hamza The string part can be considered as an inline comment.

[Lenormju]

Not very "pythonic" but it does what is asked. Works in any Python version.