I am having to load and handle strings from an external data source that are delimited by double backslash. I need to return the sorted and de-duplicated delimited string e.g. input_string = ‘bananas\\apples\\pears\\apples\\bananas\\pears’ the return string should be: ‘apples\\bananas\\pears’ …

What incorrect result do you get? Here’s what I see: In [1]: def dedupe_and_sort(input_string, delimiter='\\'): ...: ''' get a list item that contains a delimited string, dedupe and sort it and pass it bac ...: k ''' ...: distinct_items = set(x.strip() for x in input_string.split(d…

[image] hc: I am having to load and handle strings from an external data source that are delimited by double backslash. I need to return the sorted and de-duplicated delimited string e.g. Does the double-backslash already exist in the file? Because the code examples are using a single backs…

[image] hc: input_string = 'bananas\\apples\\pears\\apples\\bananas\\pears' How many backslashes do you think are actually in this string? There are five, not ten. If you actually see bananas\\apples\\pears\\apples\\bananas\\pears when you, for example, save the data from the “external data…

[image] Karl Knechtel: You need to make sure of what the delimiter actually is, in the actual data that you have. The code that you show works fine for the test data that you show. in the SQL table there’s basically field stuffing going on and the string literal in the table column would be b…

Based on that, it seems like you understand the difference between "\\\\" (two backslashes, escaped) and "\\" (just one). So where’s the confusion? In the first example, you are splitting a string with single backslashes, and joining it with doubled ones. So you get the expected output. In the seco…

[image] James Webber: to clarify more, the string you have defined as input_string doesn’t have the doubled backslashes in it. If you print it out you will see that. Of course, silly me getting confused with visual presentation vs underlying content. Thx. In hindsight the answer is pretty o…

Surprisingly, no-one has pointed out that raw-string literals are useful when typing strings in your code that contain backslash (but don’t need to represent special characters like newline). It basically turns off the backslash-escape convention, so the visual confusion is less. Then the string yo…

[image] Jeff Allen: It basically turns off the backslash-escape convention, so the visual confusion is less. Do keep in mind that raw string literals do still use backslash to prevent a quote that comes immediately after from terminating the string - but they don’t “escape” the quote when doi…

[image] Karl Knechtel: This happens because Python considers the backslash when it tokenizes the code, to figure out where the string ends; then it determines what the string actually contains on a later pass, taking the r prefix into account. This explains a lot, thank you! I had a problem w…

Backslashes can be nasty. You can find a good explanation here: Backslashes [image] I searched my .bash_history for the line with the highest ratio of special characters to regular alphanumeric characters, and the winner was: cat out.txt | grep -o "[[(].*[])][^)]]*$" ... I have no memory…

How to handle '\\' as a delimiter in Python strings

Python Help

hansgeunsmeyer (Hans Geuns-Meyer) September 2, 2023, 12:33pm 11

Backslashes can be nasty. You can find a good explanation here: