how to detect comment in source code file ?

[vnkumbhani]

how works python interpreter for finding comment ?
if possible find nested comment ?

 

[Paul Rudin]

It works as specified in the language reference. In particular, see


Python's comments are line-end comments only. The syntax does not allow
multi-line nor nested comments.

Although you can use unbound multi-line strings as a kind of
comment. But its often better to make the strings into doc strings
proper.

 

[Steven D'Aprano]

It works as specified in the language reference. In particular, see


Python's comments are line-end comments only. The syntax does not allow
multi-line nor nested comments.

While that's technically true, you can use bare strings as de facto
comments. The compiler drops any bare strings it sees, so one can nest
pseudo-comments like this:


do_this()
"""
do_that()
do_something() # Make the widget work correctly.
'''
for x in range(5):
do_something_else()
'''
do_something_different()
"""


In the above, everything except do_this() is commented out by being
turned into a string.

 

[Dennis Lee Bieber]

how works python interpreter for finding comment ?
if possible find nested comment ?

Python does not have "nested comment". Comments begin at any #
character that is not inside a string (something inside ' or " pairs).

 

[Vincent Vande Vyvre]

Le 04/09/2013 08:05, (e-mail address removed) a écrit :

how works python interpreter for finding comment ?
if possible find nested comment ?

If you need to find it yourself, you can use the module tokenize.

ex.:
---------------------------------------------------------------
import tokenize
from StringIO import StringIO

script = "# importing comment\nfrom foo import baz"\
"if baz.vers < 2:\n AUTO = False # Retrocompatibility"

def find_comment():
print script
cmt = tokenize.COMMENT
tokens = tokenize.generate_tokens(StringIO(script).readline)
for typ, _, begin, _, _ in tokens:
if typ == cmt:
print 'Find comment line %s at column %s' % begin

find_comment()

 

[Piet van Oostrum]

Python does not have "nested comment". Comments begin at any #
character that is not inside a string (something inside ' or " pairs).

You could consider this a kind of nested comment

# if condition:
# # calculate the amount
# amount = sum(parts)