[Python-projects] yield != return

[Sylvain Thénault]

On Tue, Sep 09, 2008 at 09:55:10AM -0500, skip at pobox.com wrote:
> Pylint seems to treat yield statements as if they were returns.  They
> definitely seem to be counted the same and the error message emitted with
> too many yields even calls them "returns":
> 
>     yieldex.py:1: [R, yield_ex] Too many return statements (10/6)
> 
> Here's a trivial example cobbled together from an actual (slightly more
> complex) functio which generates a Python function from a higher level
> input:
> 
>     def yield_ex(s):
>         if s:
>             yield "    line 1: %s\n" % s
>             yield "    line 2\n"
>             yield "    line 3\n"
>             yield "    line 4\n"
>             yield "    line 5\n"
>         else:
>             yield "    line 6\n"
>             yield "    line 7\n"
>             yield "    line 8\n"
>             yield "    line 9\n"
>             yield "    line 10\n"
> 
> I found it convenient to yield each line of the generated function.  The
> code is hardly more complex than the above though there are some parameter
> substitutions on several lines.  Having just two yield statements would have
> made it less obvious which values were being substituted where.  (Though I
> will admit I could have used dict format expansion.)
> 
> At any rate, I don't think yield statements should be counted the same way
> returns are.

True. I've added a ticket: http://www.logilab.oorg/ticket/5977 

One possibility is to count subsequent yield as one. Another to don't have 
this kind of warning for yield. Opinion ?

-- 
Sylvain Thénault                               LOGILAB, Paris (France)
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