python-patterns/template.py at master · rishid/python-patterns · GitHub

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'''http://ginstrom.com/scribbles/2007/10/08/design-patterns-python-style/'''

"""An example of the Template pattern in Python"""

ingredients="spam eggs apple"
line='-'*10

# Skeletons
defiter_elements(getter, action):
"""Template skeleton that iterates items"""
forelementingetter():
action(element)
print(line)

defrev_elements(getter, action):
"""Template skeleton that iterates items in reverse order"""
forelementingetter()[::-1]:
action(element)
print(line)

# Getters
defget_list():
returningredients.split()

defget_lists():
return [list(x) forxiningredients.split()]

# Actions
defprint_item(item):
print(item)

defreverse_item(item):
print(item[::-1])

# Makes templates
defmake_template(skeleton, getter, action):
"""Instantiate a template method with getter and action"""
deftemplate():
skeleton(getter, action)
returntemplate

# Create our template functions
templates= [make_template(s, g, a)
forgin (get_list, get_lists)
forain (print_item, reverse_item)
forsin (iter_elements, rev_elements)]

# Execute them
fortemplateintemplates:
template()