Python f-string: replacing newline/linebreak
Question:
First off all, sorry: I’m quite certain this might be a “duplicate” but I didn’t succeed finding the right solution.
I simply want to replace all linebreaks within my sql-code for logging it to one line, but Python’s f-string doesn’t support backslashes, so:
# Works fine (but is useless ;))
self.logger.debug(f"Executing: {sql.replace( 'C','XXX')}")
# Results in SyntaxError:
# f-string expression part cannot include a backslash
self.logger.debug(f"Executing: {sql.replace( 'n',' ')}")
Of course there are several ways to accomplish that before the f-string, but I’d really like to keep my “log the line”-code in one line and without additional helper variables.
(Besides I think it’s a quite stupid behavior: Either you can execute code within the curly brackets or you cant’t…not “you can, but only without backslashes”…)
This one isn’t a desired solution because of additional variables:
How to use newline 'n' in f-string to format output in Python 3.6?
General Update
The suggestion in mkrieger1s comment:
self.logger.debug("Executing %s", sql.replace('n',' '))
Works fine for me, but as it doesn’t use f-strings at all (beeing that itself good or bad ;)), I think I can leave this question open.
Answers:
You can do this
newline = 'n'
self.logger.debug(f"Executing: {sql.replace( newline,' ')}")
- don’t use f-strings, especially for logging
- assign the newline to a constant and use that, which you apparently don’t want to
- use an other version of expressing a newline,
chr(10) for instance
(Besides I think it’s a quite stupid behavior: Either you can execute code within the curly brackets or you cant’t…not “you can, but only without backslashes”…)
Feel free to take a shot at fixing it, I’m pretty sure this restriction was not added because the PEP authors and feature developers wanted it to be a pain in the ass.
I found possible solutions
from os import linesep
print(f'{string_with_multiple_lines.replace(linesep, " ")}')
Best,
First off all, sorry: I’m quite certain this might be a “duplicate” but I didn’t succeed finding the right solution.
I simply want to replace all linebreaks within my sql-code for logging it to one line, but Python’s f-string doesn’t support backslashes, so:
# Works fine (but is useless ;))
self.logger.debug(f"Executing: {sql.replace( 'C','XXX')}")
# Results in SyntaxError:
# f-string expression part cannot include a backslash
self.logger.debug(f"Executing: {sql.replace( 'n',' ')}")
Of course there are several ways to accomplish that before the f-string, but I’d really like to keep my “log the line”-code in one line and without additional helper variables.
(Besides I think it’s a quite stupid behavior: Either you can execute code within the curly brackets or you cant’t…not “you can, but only without backslashes”…)
This one isn’t a desired solution because of additional variables:
How to use newline 'n' in f-string to format output in Python 3.6?
General Update
The suggestion in mkrieger1s comment:
self.logger.debug("Executing %s", sql.replace('n',' '))
Works fine for me, but as it doesn’t use f-strings at all (beeing that itself good or bad ;)), I think I can leave this question open.
You can do this
newline = 'n'
self.logger.debug(f"Executing: {sql.replace( newline,' ')}")
- don’t use f-strings, especially for logging
- assign the newline to a constant and use that, which you apparently don’t want to
- use an other version of expressing a newline,
chr(10)for instance
(Besides I think it’s a quite stupid behavior: Either you can execute code within the curly brackets or you cant’t…not “you can, but only without backslashes”…)
Feel free to take a shot at fixing it, I’m pretty sure this restriction was not added because the PEP authors and feature developers wanted it to be a pain in the ass.
I found possible solutions
from os import linesep
print(f'{string_with_multiple_lines.replace(linesep, " ")}')
Best,