>But what's got that to do with it? Strings are very mutable in C. I realized after posting that I'd said something incorrect again. The concept of "mutability" itself is a high-level concept compared to C. Memory allocation for strings is expensive because of the way malloc() works to find a "best-fit" against a "first-fit" in traditional memory management systems. Because of the performance hit, high level languages and frameworks, such as the Common Type System of the .NET Framework for example, considers strings as immutable. That, unlike Python, doesn't however, make them impossible to modify in-place.
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