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<H2><A NAME="SECTION0051210000000000000000"><!--x--></A><A NAME="traceback-example"><!--z--></A>
<BR>
3.12.1 Traceback Example
</H2>
<P>
This simple example implements a basic read-eval-print loop, similar
to (but less useful than) the standard Python interactive interpreter
loop. For a more complete implementation of the interpreter loop,
refer to the <tt class="module"><a href="module-code.html">code</a></tt> module.
<P>
<div class="verbatim"><pre>
import sys, traceback
def run_user_code(envdir):
source = raw_input(">>> ")
try:
exec source in envdir
except:
print "Exception in user code:"
print '-'*60
traceback.print_exc(file=sys.stdout)
print '-'*60
envdir = {}
while 1:
run_user_code(envdir)
</pre></div>
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<span class="release-info">Release 2.3.4, documentation updated on May 20, 2004.</span>
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