import re

text = "this is a bunch of things ab3e ab12e abc2e abc12e abc2ed ab12ed"

# computingID_regex = re.compile(r"[a-z]{2,3}[0-9][a-z]{1,2}")
computingID_regex = re.compile(r"\w{2,3}\d\w{1,2}")


print("=== example: search() ===")
# search() returns the first occurrence of that matched object
#   including start and end indices, and the matched string
search_result = computingID_regex.search(text)
print(search_result)
print(type(search_result))    # <class '_sre.SRE_Match'>

# group() returns the matched object
print(search_result.group())
print(type(search_result.group()))    # <class 'str'>

# start() returns the first index of the match
print(search_result.start())
print(type(search_result.start()))    # <class 'int'>

# end() returns the last index of the match
print(search_result.end())
print(type(search_result.end()))      # <class 'int'>


print("=== example: match() ===")
# match() checks if the pattern exists at the beginning of a given string
#   returns None if pattern not found (python processes it as False)
#   otherwise, returns the matched object
#       thus supporting group(), start(), and end()
match_result = computingID_regex.match(text)
print(match_result)


print("=== example: findall() ===")
# findall() returns a list of strings of all non-overlapping matches
#   of the pattern in a given string
findall_result = computingID_regex.findall(text)
print(findall_result)
print(type(findall_result))           # <class 'list'>

print("--- loop to print result from findall() ---")
for str in findall_result:
    print(str)


print("=== example: finditer() ===")
# finditer() returns a list (or iterator) of matched objects
#   thus supporting group(), start(), and end()
finditer_result = computingID_regex.finditer(text)
print(finditer_result)
print(type(finditer_result))          # <class 'callable_iterator'>

print("--- loop print result from finditer() ---")
for obj in finditer_result:
    print(obj, obj.group(), obj.start(), obj.end())