Difference between revisions of "Python:Control structures"
Jump to navigation
Jump to search
Line 2: | Line 2: | ||
Most flow control is standard. Indentation defines the code block to execute. You must be strict, all indents must be the same in a block, a mix of spaces and tabs is not allowed (unless each line uses the same mix). | Most flow control is standard. Indentation defines the code block to execute. You must be strict, all indents must be the same in a block, a mix of spaces and tabs is not allowed (unless each line uses the same mix). | ||
+ | |||
+ | You can define you own [[Python:Functions]] too. | ||
<syntaxhighlight lang=python> | <syntaxhighlight lang=python> |
Revision as of 14:45, 24 January 2020
Most flow control is standard. Indentation defines the code block to execute. You must be strict, all indents must be the same in a block, a mix of spaces and tabs is not allowed (unless each line uses the same mix).
You can define you own Python:Functions too.
if expression:
block
else:
otherblock
for var1 in itterable: # keys if itterable is a dict
block
if somethinghappens:
break
pass
- No operation, use e.g. to avoid negative tests
Exception handling
To catch exceptions:
try:
blockthatmaythowexception
except <exception>:
blockifexceptionisthrown
else:
blockifNOexceptionisthrown
Specifying an exception is optional but highly recommended. The exceptiontypes can be found in the python docs
- except NameError
- The variable does not exist
- except KeyError
- The key does not exist in the dict
- except IndexError
- The index does not exist in the list