Embedded assignments

I was advised against using embedded assignments, such as the following:

printf("area equals %f", area = length * width);

I certainly understand the point of not using such a construction in the many cases where the clarity of the code to the reader might suffer, but personally, in SOME cases, I find it easier to read these types of assignments, much like it's sometimes more clear to write one long sentence, rather than to break up related ideas into two separate sentences. I was wondering whether there were any functional reason OTHER than readability that it would be a bad idea to use embedded assignments. Thanks ahead for your help!

Code:

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//original statement
printf("area equals %f", area = length * width);

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Try making this adjustment:

Code:

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printf("area equals %f", length * width);

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Or even this:

Code:

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printf("area equals %f", Area());
...
float Area(float length, float width)
{
  return length * width;
}

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