Professional IronPython

Working with Existing Objects
 
❘
 
81
to search for the first occurrence of l within a string, you’d type 
MyString.find(‘l‘)
. This 
method returns a value of –1 when the string doesn’t contain the search value.
➤
➤
format(*args[, *kwargs])
: Formats the string using a template (see the “Formatting 
String Output” section for details). The 
args
argument contains positional information and 
kwargs
contains a keyword argument.
➤
➤
index(str sub[, int start[, int end]])
 or
index(str sub, object start, object end)
: Performs precisely the same task as 
find()
. However, instead of returning –1 when a value isn’t found, 
index()
raises a 
ValueError
instead.
➤
➤
isalnum()
, 
isalpha()
, 
isdecimal()
, 
isdigit()
, 
islower()
, 
isnumeric()
, 
isspace()
, 
istitle()
, 
isunicode()
, and 
isupper()
: Detects the state of the string and returns True 
when the specified condition exists. For example, 
isalnum()
returns 
True
when a string con-
tains some combination of letters and numbers. The string must contain at least one letter, 
but need not necessarily contain any numbers. The 
isalpha()
method, on the other hand, 
only returns 
True
when the string contains only letters, and 
isnumeric()
returns 
True
when 
the string contains only numbers.
➤
➤
join(list sequence)
 or 
join(object sequence)
: Appends a string to a list or a sequence. 
This method joins each member of the sequence to the source string. For example, if the source 
string contains ABC and you join 123 to it, you obtain ‘1ABC2ABC3’ as output. To obtain
this output, you’d type 
MyString.join(‘123‘)
. As an alternative, you could type 
MyString 
.join([‘1‘, ‘2‘, ‘3‘])
to obtain the same output using a list.
➤
➤