Python templates
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Python string templates using the % template operator
Python has an excellent built-in template system -- the % operator. Granted this is not what many people would consider a "real" template system, but it's much more powerful than most people give it credit for.
The key is to combine % with the locals() function. Template code practically writes itself. Remember string templates can have more than just %d and %s style replacements. It can also take a dictionary, like %(DICT_KEY1)s or %(DICT_KEY2)d. Next remember that the locals() function returns a dictionary of local variables. This makes it trivial to merge local variables into a string template.
# This is a string template to format an email. TEMPLATE="""From: %(FROM)s To: %(TO)s Hello %(USERNAME)s, Subject: %(SUBJECT)s Your account is over quota. Your quota limit is %(LIMIT)d bytes. Your amount used is %(USED)d bytes. """ def send_alert (USERNAME, FROM, TO, SUBJECT, LIMIT, USED): return TEMPLATE % locals()
Running the template will give the following results:
>>> print send_alert ('Joe Bloe', 'root@example.com', 'jbloe@example.com', 'over quota', 1000, 1234) From: root@example.com To: jbloe@example.com Hello Joe Bloe, Subject: over quota Your account is over quota. Your quota limit is 1000 bytes. Your amount used is 1234 bytes. >>>