What is a raw representation?

Question

I'm reading "Learn Python the hard way" (by Zed Shaw) and it says that %r is used for "raw representation and debugging".

I'm sorry for such a uninformed question, but I have no idea what does it mean.

It's the representation returned form the `repr` function. It's similar to `str` but intended for internal use rather than display. It can be useful to print an element regardless of its type. [related](http://stackoverflow.com/questions/1436703/difference-between-str-and-repr-in-python) — Paul Rooney, Feb 27 '17 at 01:38
@cricket I'm expecting it to be shut down as a dupe at any moment, so didnt think an answer was appropriate — Paul Rooney, Feb 27 '17 at 01:41

score 0 · Accepted Answer · answered Feb 27 '17 at 01:48

So you know %s is used for most strings, that just calls str() over the variable that is formatted.

repr(), on the other hand is used for %r and will return the "raw string", which is easiest seen on string variables.

>>> print("%r vs. %s" % ('42','42'))
'42' vs. 42

'r' - String (converts any Python object using repr()).
's' - String (converts any Python object using str()).

When it says it is useful for "debugging", imagine you had leading/trailing spaces in a string... the "raw" format would be more clear.

print("%r vs. %s" % ('  hello','  hello'))
'  hello' vs.   hello

Thank you! That was very helpful – Fallingtoo Feb 28 '17 at 01:46 — Fallingtoo, Feb 28 '17 at 01:46

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