[Python-Dev] cpython: Remove some extraneous parentheses and swap the comparison order to (original) (raw)

David Malcolm dmalcolm at redhat.com
Tue Jun 7 23:35:29 CEST 2011

On Tue, 2011-06-07 at 11:03 +0200, M.-A. Lemburg wrote:

Georg Brandl wrote: > On 06/07/11 05:20, brett.cannon wrote: >> http://hg.python.org/cpython/rev/fc282e375703 >> changeset: 70695:fc282e375703 >> user: Brett Cannon <brett at python.org> >> date: Mon Jun 06 20:20:36 2011 -0700 >> summary: >> Remove some extraneous parentheses and swap the comparison order to >> prevent accidental assignment. >> >> Silences a warning from LLVM/clang 2.9. > > Swapping the comparison order here seems a bit inconsistent to me. There are > lots of others around (e.g. "len == 0" in the patch context below). Why is > this one so special? > > I think that another developer even got told off once for these kinds of > comparisons. > > I hope the Clang warning is only about the parentheses.

I agree with Georg: "if ('u' == typecode)" is not well readable, since you usually put the variable part on the left and the constant part on the right of an equal comparison.

[FWIW, I'm one of the reprobates that likes to put the constant on the LHS when I'm coding in C, but I see I'm in the minority here]

I know that this style is unpopular, but if it helps, try mentally pronouncing "==" in C as "is the value of".

In this example, when I read that line, my mind is thinking:

"if 'u' is the value of typecode"

After ~12 years of doing this, it comes naturally. I appreciate that this may come across as weird though :)

[snip]

Hope this is helpful Dave

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