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\usepackage{multirow}
\usepackage{ifthen}
\usepackage[colorlinks=true,linkcolor=blue,urlcolor=blue]{hyperref}
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\newcommand{\titlereference}[1]{\textsl{#1}}
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\input{pygments-default.sty}
\title{Example for syntax highlight with Pygments}
\author{}
\date{}
\hypersetup{
pdftitle={Example for syntax highlight with Pygments}
}
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\begin{document}
\maketitle


\setlength{\locallinewidth}{\linewidth}
% # -*- rst-mode -*- 

Translate this document to HTML with a pygments enhanced frontend:
\begin{quote}{\ttfamily \raggedright \noindent
rst2html-pygments~-{}-stylesheet=pygments-default.css
}\end{quote}

or to LaTeX with:
\begin{quote}{\ttfamily \raggedright \noindent
rst2latex-pygments~-{}-stylesheet=pygments-default.sty
}\end{quote}

to gain syntax highlight in the output.
% Run the doctests with ``pylit --doctest for-else-test.py``. 


%___________________________________________________________________________

\hypertarget{for-else-test}{}
\pdfbookmark[0]{for-else-test}{for-else-test}
\section*{for-else-test}

Test the flow in a \titlereference{for} loop with \titlereference{else} statement.

First define a simple \titlereference{for} loop.
\begin{Verbatim}[commandchars=@\[\]]
@Cax[def] @CaJ[loop1](iterable):
    @Car["""simple for loop with `else` statement"""]
    @Cax[for] i @Cam[in] iterable:
        @Cax[print] i
    @Cax[else]:
        @Cax[print] @Cad["]@Cad[iterable empty]@Cad["]
    @Cax[print] @Cad["]@Cad[Ende]@Cad["]

\end{Verbatim}

Now test it:

The first test runs as I expect: iterator empty -{\textgreater} else clause applies:
\begin{Verbatim}[commandchars=@\[\]]
@CaN[>>> ]loop1(@CaW[range](@Cag[0]))
@Caa[iterable empty]
@Caa[Ende]

\end{Verbatim}

However, the else clause even runs if the iterator is not empty in the first
place but after it is ``spent'':
\begin{Verbatim}[commandchars=@\[\]]
@CaN[>>> ]loop1(@CaW[range](@Cag[3]))
@Caa[0]
@Caa[1]
@Caa[2]
@Caa[iterable empty]
@Caa[Ende]

\end{Verbatim}

It seems like the else clause can only be prevented, if we break out of
the loop. Let's try
\begin{Verbatim}[commandchars=@\[\]]
@Cax[def] @CaJ[loop2](iterable):
    @Car["""for loop with `break` and `else` statement"""]
    @Cax[for] i @Cam[in] iterable:
        @Cax[print] i
        @Cax[break]
    @Cax[else]:
        @Cax[print] @Cad["]@Cad[iterable empty]@Cad["]
    @Cax[print] @Cad["]@Cad[Ende]@Cad["]

\end{Verbatim}

And indeed, the else clause is skipped after breaking out of the loop:
\begin{Verbatim}[commandchars=@\[\]]
@CaN[>>> ]loop2(@CaW[range](@Cag[3]))
@Caa[0]
@Caa[Ende]

\end{Verbatim}

The empty iterator runs as expected:
\begin{Verbatim}[commandchars=@\[\]]
@CaN[>>> ]loop2(@CaW[range](@Cag[0]))
@Caa[iterable empty]
@Caa[Ende]

\end{Verbatim}

\begin{center}\small

Generated on: 2007-04-24.


\end{center}

\end{document}