Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
84 views
in Technique[技术] by (71.8m points)

Failed to catch syntax error python


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

You can only catch SyntaxError if it's thrown out of an eval, exec, or import operation.

>>> try:
...    eval('x === x')
... except SyntaxError:
...    print "You cannot do that"
... 
You cannot do that

This is because, normally, the interpreter parses the entire file before executing any of it, so it detects the syntax error before the try statement is executed. If you use eval or its friends to cause more code to be parsed during the execution of the program, though, then you can catch it.

I'm pretty sure this is in the official manual somewhere, but I can't find it right now.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...