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Re: operator precedence differs from C language


On 03/31/2010 07:36 PM, Neo Liu wrote:
> I found that the operator precedence of "&" and "==" differed from C
> language. Take a look at the following statements.

That's not true -- in C and in stap, relational operators bind more
tightly than bitwise operators.  http://tinyurl.com/9q6szp

Here's a program to convince yourself of this:

#include <stdio.h>
#define TEST(e) printf("( %s ) = %d\n", #e, e)
int main(int argc, const char *argv[])
{
    if (argc < 2) return 1;
    int x = atoi(argv[1]);
    TEST(x);
    TEST(x & 07);
    TEST((x & 07) == 0);
    TEST(x & (07 == 0));
    TEST(x & 07 == 0);
    return 0;
}


Josh


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