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# Example for syntax highlight with Pygments
# ==========================================
#
# Translate this document to HTML with a pygments enhanced frontend::
#
# rst2html-pygments --stylesheet=pygments-default.css
#
# or to LaTeX with::
#
# rst2latex-pygments --stylesheet=pygments-default.sty
#
# to gain syntax highlight in the output.
#
# .. Run the doctests with ``pylit --doctest for-else-test.py``.
#
#
# for-else-test
# -------------
#
# Test the flow in a `for` loop with `else` statement.
#
# First define a simple `for` loop.
#
# .. code-block:: python
def loop1(iterable):
"""simple for loop with `else` statement"""
for i in iterable:
print i
else:
print "iterable empty"
print "Ende"
# Now test it:
#
# The first test runs as I expect: iterator empty -> else clause applies:
#
# .. code-block:: pycon
#
# >>> loop1(range(0))
# iterable empty
# Ende
#
# However, the else clause even runs if the iterator is not empty in the first
# place but after it is "spent":
#
# .. code-block:: pycon
#
# >>> loop1(range(3))
# 0
# 1
# 2
# iterable empty
# Ende
#
# It seems like the else clause can only be prevented, if we break out of
# the loop. Let's try
#
# .. code-block:: python
def loop2(iterable):
"""for loop with `break` and `else` statement"""
for i in iterable:
print i
break
else:
print "iterable empty"
print "Ende"
# And indeed, the else clause is skipped after breaking out of the loop:
#
# .. code-block:: pycon
#
# >>> loop2(range(3))
# 0
# Ende
#
# The empty iterator runs as expected:
#
# .. code-block:: pycon
#
# >>> loop2(range(0))
# iterable empty
# Ende
#
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