Question

Text File contents:

&CRB  A='test1'   B=123,345, 678   &END
Misc text potentially between entries ...
&CRB  A='test2'   
             B=788, 345, 3424   &END
&CRB  A='test3'   
             B=788, 345, 3424   &END
&CRB  A='test4' B=788, 345, 3424   &END

What is the most efficient way to iterate through the entries between the keywords? Note
that some entries span lines. Something like the following is desired –

f = open(filename)
for entry in f:
    - do something with entry

Of course it is not that easy. But, are there suggestions on a straightforward way to iterate thorough the entries delimiated by two key words.

Answer 1

Assuming that the entry is all of the text between &CRB and &END pairs, you can pull out the text between them with something like this:

import re

# the regular expression treats newlines as a regular character, so the
# multiline entries are okay. It's non-greedy, so it gets individual entries.
pat = re.compile(r'&CRB(.+?)&END',  re.DOTALL)

s = ''' &CRB  A='test1'   B=123,345, 678   &END
Misc text potentially between entries ...
&CRB  A='test2'   
             B=788, 345, 3424   &END
&CRB  A='test3'   
             B=788, 345, 3424   &END
&CRB  A='test4' B=788, 345, 3424   &END'''

for entry in pat.findall(s):
   # do something with each entry
   print entry

prints this:

 A='test1'   B=123,345, 678   
  A='test2'   
             B=788, 345, 3424   
  A='test3'   
             B=788, 345, 3424   
  A='test4' B=788, 345, 3424  

…it’s your problem to clean up and interpret the contents of each of those records…