Evaluation inside string

Is there something like Rubys "Hello #{userNameFu开发者_JS百科nction()}" in python?

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In Python, you would use string interpolation

"Hello %s" % user_name_function()

or string formating

"Hello {0}".format(user_name_function())

The latter is available in Python 2.6 or above.

Also note that by convention you don't use CamelCase for function names in Python (CamelCase is for class names only -- see PEP 8).

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Python's string interpolation is the closest to what you want.

The most common form is:

>>> "Hello %s" % userNameFunction()
'Hello tm1brt'

This makes use of a tuple to supply the data in the order they are needed in the string.

But, you can also use a dict and use meaningful names for the data that you need inside the string:

>>> "Hello %(name)s" % {'name' : userNameFunction()}
'Hello tm1brt'

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In Python 2.4+ you can use the Templateclass in the stringmodule to do things like this:

from string import Template

def user_name_function(): return "Dave"

s = Template('Hello $s')
print s.substitute(s=user_name_function())
# 'Hello Dave'

print s.substitute({'s': user_name_function()})
# 'Hello Dave'