[Python-Dev] Visibility scope for "for/while/if" statements

Josiah Carlson jcarlson at uci.edu
Thu Sep 22 22:58:08 CEST 2005

Alexander Myodov <maa_public at sinn.ru> wrote:

> >> "for (int i = 0; i < 10; i++)" works fine nowadays.
> JC> I'm sorry, but you are wrong.  The C99 spec states that you must define
> JC> the type of i before using it in the loop.  Maybe you are thinking of
> JC> C++, which allows such things.
> "gcc -std=c99" compiles the line "for (int i = 0; i <= 5; i++);"
> perfectly. Along with another sample mentioned above   .
> To this day, I relied upon gcc in terms of standards compatibility...

I misread the error message from my compiler.  It /only/ works in C99
mode.  Previous C standards (which CPython itself conforms to) did not
allow such things.

Interestingly enough, not all C++ compilers (Microsoft) hid variables
created in for loops

 - Josiah

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