''' Demonstrate functions can be pass with function parameter
'''

def analyze( x, f ) :   # analyze takes in two parameters x (a list of values) and f (a function identifier)
    ''' Return the result of f( x )
    '''
    print( 'id(f) = ', id(f) )
    result = f( x ) # Since functions are first class (can be used as variables), we can basically
                    # use the function name passed in as a callable function and call it on the list x
                    # ex. back in spooky if called functions_are_first_class.analyze(values, min)
                    # it will find the min(x) / min(values) since values is the argument to x

    return result

# Purpose: functions can be used as variables so that we can use them as callable variables.
# We can pass in a function of choice using another function and call that function
# so if the function parameter is f then we call the function f
# in the function using f( x ) where we pass in x into that function f (whatever that function is)
# In the spooky.py tester, we pass in len, max, min, sum as f and call it on the argument values as
# list x.

# Uncomment this code to see how it works! You should get 'hello'
# s = '    hello '
# words = s.strip
# words is now a callable variable that stores the function identifier.
# We can call s.strip() by just doing:
# words()
# since words = s.strip

# Test functions may include:
    # Calculations
    # Accumulator Problems
        # Functions that produce lists
        # Functions that produce strings
        # Functions that produce numbers
    # Dataset problems
    # Dictionary Problems
# I would recommend going over practice test problems found under Testing on the webppage
# in order to get a good grasp of the kinds of function questions for the coding portion
# we might ask. Practice makes you get better and faster :)