I'm trying to understand how I should read python documentation, for example given:
string.lstrip(s[, chars])
How should I read that? I know that brackets means optional, but that 's', what does it mean? Is there a page where it explains how the documentation was written?
1 Answer
It's not explictly defined in the documentation, but in
string.lstrip(s[, chars])
string is a Python module, it is not any string (e.g. it can't be "abc").
The parameter s is the string (e.g. it can be "abc") that you want to strip. It's mandatory, not optional.
The bracket-enclosed parameter is optional, it will be a string and its characters will be stripped from the string.
Some examples of how to call this function are:
import string
print string.lstrip("abc", "a") # "bc"
print string.lstrip(" abc") # "abc"
Note: Don't confuse with "abc".lstrip(). They are different functions with identical results. Also, read @user2357112's comment.
Edit: On my IDE I've just tested it and it actually shows what is s on the docs (pressing F2):
def lstrip Found at: string
def lstrip(s, chars=None):
"""lstrip(s [,chars]) -> string
Return a copy of the string s with leading whitespace removed.
If chars is given and not None, remove characters in chars instead.
"""
return s.lstrip(chars)
# Strip trailing tabs and spaces
1 Comment
user2357112
Note that the documentation explicitly says not to use this: "The following list of functions are also defined as methods of string and Unicode objects; see section String Methods for more information on those. You should consider these functions as deprecated, although they will not be removed until Python 3."
sis the function's first parameter. There's nothing significant about the choice of the letters; it's just a name.str.lstripis something else. That method only takes a single, optional argument.stringmodule, not a string variable. It is literally "string".